---
_id: '31294'
article_number: '101501'
author:
- first_name: Tobias
  full_name: Weich, Tobias
  id: '49178'
  last_name: Weich
  orcid: 0000-0002-9648-6919
citation:
  ama: Weich T. Equivariant spectral asymptotics for<i>h</i>-pseudodifferential operators.
    <i>Journal of Mathematical Physics</i>. 2014;55(10). doi:<a href="https://doi.org/10.1063/1.4896698">10.1063/1.4896698</a>
  apa: Weich, T. (2014). Equivariant spectral asymptotics for<i>h</i>-pseudodifferential
    operators. <i>Journal of Mathematical Physics</i>, <i>55</i>(10), Article 101501.
    <a href="https://doi.org/10.1063/1.4896698">https://doi.org/10.1063/1.4896698</a>
  bibtex: '@article{Weich_2014, title={Equivariant spectral asymptotics for<i>h</i>-pseudodifferential
    operators}, volume={55}, DOI={<a href="https://doi.org/10.1063/1.4896698">10.1063/1.4896698</a>},
    number={10101501}, journal={Journal of Mathematical Physics}, publisher={AIP Publishing},
    author={Weich, Tobias}, year={2014} }'
  chicago: Weich, Tobias. “Equivariant Spectral Asymptotics for<i>h</i>-Pseudodifferential
    Operators.” <i>Journal of Mathematical Physics</i> 55, no. 10 (2014). <a href="https://doi.org/10.1063/1.4896698">https://doi.org/10.1063/1.4896698</a>.
  ieee: 'T. Weich, “Equivariant spectral asymptotics for<i>h</i>-pseudodifferential
    operators,” <i>Journal of Mathematical Physics</i>, vol. 55, no. 10, Art. no.
    101501, 2014, doi: <a href="https://doi.org/10.1063/1.4896698">10.1063/1.4896698</a>.'
  mla: Weich, Tobias. “Equivariant Spectral Asymptotics for<i>h</i>-Pseudodifferential
    Operators.” <i>Journal of Mathematical Physics</i>, vol. 55, no. 10, 101501, AIP
    Publishing, 2014, doi:<a href="https://doi.org/10.1063/1.4896698">10.1063/1.4896698</a>.
  short: T. Weich, Journal of Mathematical Physics 55 (2014).
date_created: 2022-05-17T12:57:00Z
date_updated: 2022-05-19T10:16:38Z
department:
- _id: '10'
- _id: '623'
- _id: '548'
doi: 10.1063/1.4896698
external_id:
  arxiv:
  - '1311.2436 '
intvolume: '        55'
issue: '10'
keyword:
- Mathematical Physics
- Statistical and Nonlinear Physics
language:
- iso: eng
publication: Journal of Mathematical Physics
publication_identifier:
  issn:
  - 0022-2488
  - 1089-7658
publication_status: published
publisher: AIP Publishing
status: public
title: Equivariant spectral asymptotics for<i>h</i>-pseudodifferential operators
type: journal_article
user_id: '49178'
volume: 55
year: '2014'
...
---
_id: '38088'
article_number: '31138'
author:
- first_name: Dror
  full_name: Shayovitz, Dror
  last_name: Shayovitz
- first_name: Harald
  full_name: Herrmann, Harald
  id: '216'
  last_name: Herrmann
- first_name: Wolfgang
  full_name: Sohler, Wolfgang
  last_name: Sohler
- first_name: Raimund
  full_name: Ricken, Raimund
  last_name: Ricken
- first_name: Christine
  full_name: Silberhorn, Christine
  id: '26263'
  last_name: Silberhorn
- first_name: Dan M.
  full_name: Marom, Dan M.
  last_name: Marom
citation:
  ama: Shayovitz D, Herrmann H, Sohler W, Ricken R, Silberhorn C, Marom DM. Real-time
    coherent detection of phase modulated ultrashort pulses after time-to-space conversion
    and spatial demultiplexing. <i>Optics Express</i>. 2014;22(25). doi:<a href="https://doi.org/10.1364/oe.22.031138">10.1364/oe.22.031138</a>
  apa: Shayovitz, D., Herrmann, H., Sohler, W., Ricken, R., Silberhorn, C., &#38;
    Marom, D. M. (2014). Real-time coherent detection of phase modulated ultrashort
    pulses after time-to-space conversion and spatial demultiplexing. <i>Optics Express</i>,
    <i>22</i>(25), Article 31138. <a href="https://doi.org/10.1364/oe.22.031138">https://doi.org/10.1364/oe.22.031138</a>
  bibtex: '@article{Shayovitz_Herrmann_Sohler_Ricken_Silberhorn_Marom_2014, title={Real-time
    coherent detection of phase modulated ultrashort pulses after time-to-space conversion
    and spatial demultiplexing}, volume={22}, DOI={<a href="https://doi.org/10.1364/oe.22.031138">10.1364/oe.22.031138</a>},
    number={2531138}, journal={Optics Express}, publisher={The Optical Society}, author={Shayovitz,
    Dror and Herrmann, Harald and Sohler, Wolfgang and Ricken, Raimund and Silberhorn,
    Christine and Marom, Dan M.}, year={2014} }'
  chicago: Shayovitz, Dror, Harald Herrmann, Wolfgang Sohler, Raimund Ricken, Christine
    Silberhorn, and Dan M. Marom. “Real-Time Coherent Detection of Phase Modulated
    Ultrashort Pulses after Time-to-Space Conversion and Spatial Demultiplexing.”
    <i>Optics Express</i> 22, no. 25 (2014). <a href="https://doi.org/10.1364/oe.22.031138">https://doi.org/10.1364/oe.22.031138</a>.
  ieee: 'D. Shayovitz, H. Herrmann, W. Sohler, R. Ricken, C. Silberhorn, and D. M.
    Marom, “Real-time coherent detection of phase modulated ultrashort pulses after
    time-to-space conversion and spatial demultiplexing,” <i>Optics Express</i>, vol.
    22, no. 25, Art. no. 31138, 2014, doi: <a href="https://doi.org/10.1364/oe.22.031138">10.1364/oe.22.031138</a>.'
  mla: Shayovitz, Dror, et al. “Real-Time Coherent Detection of Phase Modulated Ultrashort
    Pulses after Time-to-Space Conversion and Spatial Demultiplexing.” <i>Optics Express</i>,
    vol. 22, no. 25, 31138, The Optical Society, 2014, doi:<a href="https://doi.org/10.1364/oe.22.031138">10.1364/oe.22.031138</a>.
  short: D. Shayovitz, H. Herrmann, W. Sohler, R. Ricken, C. Silberhorn, D.M. Marom,
    Optics Express 22 (2014).
date_created: 2023-01-23T11:05:08Z
date_updated: 2023-01-30T12:07:13Z
department:
- _id: '288'
- _id: '15'
- _id: '623'
- _id: '230'
doi: 10.1364/oe.22.031138
intvolume: '        22'
issue: '25'
keyword:
- Atomic and Molecular Physics
- and Optics
language:
- iso: eng
publication: Optics Express
publication_identifier:
  issn:
  - 1094-4087
publication_status: published
publisher: The Optical Society
status: public
title: Real-time coherent detection of phase modulated ultrashort pulses after time-to-space
  conversion and spatial demultiplexing
type: journal_article
user_id: '26263'
volume: 22
year: '2014'
...
---
_id: '42025'
author:
- first_name: G
  full_name: Bulgarini, G
  last_name: Bulgarini
- first_name: M.E
  full_name: Reimer, M.E
  last_name: Reimer
- first_name: M. Bouwes
  full_name: Bavinck, M. Bouwes
  last_name: Bavinck
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: D
  full_name: Dalacu, D
  last_name: Dalacu
- first_name: P.J
  full_name: Poole, P.J
  last_name: Poole
- first_name: E.P.A.M
  full_name: Bakkers, E.P.A.M
  last_name: Bakkers
- first_name: V
  full_name: Zwiller, V
  last_name: Zwiller
citation:
  ama: Bulgarini G, Reimer ME, Bavinck MB, et al. Nanowire waveguides launching single
    photons in a Gaussian mode for ideal fiber-coupling. 2014;14(7):4102-4106.
  apa: Bulgarini, G., Reimer, M. E., Bavinck, M. B., Jöns, K. D., Dalacu, D., Poole,
    P. J., Bakkers, E. P. A. M., &#38; Zwiller, V. (2014). <i>Nanowire waveguides
    launching single photons in a Gaussian mode for ideal fiber-coupling</i> (Vol.
    14, Issue 7, pp. 4102–4106).
  bibtex: '@article{Bulgarini_Reimer_Bavinck_Jöns_Dalacu_Poole_Bakkers_Zwiller_2014,
    series={Nano Lett. }, title={Nanowire waveguides launching single photons in a
    Gaussian mode for ideal fiber-coupling}, volume={14}, number={7}, author={Bulgarini,
    G and Reimer, M.E and Bavinck, M. Bouwes and Jöns, Klaus D. and Dalacu, D and
    Poole, P.J and Bakkers, E.P.A.M and Zwiller, V}, year={2014}, pages={4102–4106},
    collection={Nano Lett. } }'
  chicago: Bulgarini, G, M.E Reimer, M. Bouwes Bavinck, Klaus D. Jöns, D Dalacu, P.J
    Poole, E.P.A.M Bakkers, and V Zwiller. “Nanowire waveguides launching single photons
    in a Gaussian mode for ideal fiber-coupling.” Nano Lett. , 2014.
  ieee: G. Bulgarini <i>et al.</i>, “Nanowire waveguides launching single photons
    in a Gaussian mode for ideal fiber-coupling,” vol. 14, no. 7. pp. 4102–4106, 2014.
  mla: Bulgarini, G., et al. <i>Nanowire waveguides launching single photons in a
    Gaussian mode for ideal fiber-coupling</i>. no. 7, 2014, pp. 4102–06.
  short: G. Bulgarini, M.E. Reimer, M.B. Bavinck, K.D. Jöns, D. Dalacu, P.J. Poole,
    E.P.A.M. Bakkers, V. Zwiller, 14 (2014) 4102–4106.
date_created: 2023-02-13T07:52:03Z
date_updated: 2023-02-13T08:44:56Z
department:
- _id: '623'
intvolume: '        14'
issue: '7'
language:
- iso: ger
page: 4102-4106
publication_status: published
series_title: 'Nano Lett. '
status: public
title: Nanowire waveguides launching single photons in a Gaussian mode for ideal fiber-coupling
type: conference
user_id: '71124'
volume: 14
year: '2014'
...
---
_id: '42024'
article_number: '5298'
author:
- first_name: M.A.M
  full_name: ' Versteegh, M.A.M'
  last_name: ' Versteegh'
- first_name: M.E
  full_name: ' Reimer, M.E'
  last_name: ' Reimer'
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: D
  full_name: Dalacu, D
  last_name: Dalacu
- first_name: P.J
  full_name: Poole, P.J
  last_name: Poole
- first_name: A
  full_name: ' Gulinatti, A'
  last_name: ' Gulinatti'
- first_name: A
  full_name: Giudice, A
  last_name: Giudice
- first_name: V
  full_name: Zwiller, V
  last_name: Zwiller
citation:
  ama: Versteegh MAM,  Reimer ME, Jöns KD, et al. Observation of strongly entangled
    photon pairs from a nanowire quantum dot. 2014;5.
  apa: Versteegh, M. A. M.,  Reimer, M. E., Jöns, K. D., Dalacu, D., Poole, P. J.,  Gulinatti,
    A., Giudice, A., &#38; Zwiller, V. (2014). <i>Observation of strongly entangled
    photon pairs from a nanowire quantum dot</i> (No. 5298; Vol. 5).
  bibtex: '@article{ Versteegh_ Reimer_Jöns_Dalacu_Poole_ Gulinatti_Giudice_Zwiller_2014,
    series={Nat. Commun.}, title={Observation of strongly entangled photon pairs from
    a nanowire quantum dot}, volume={5}, number={5298}, author={ Versteegh, M.A.M
    and  Reimer, M.E and Jöns, Klaus D. and Dalacu, D and Poole, P.J and  Gulinatti,
    A and Giudice, A and Zwiller, V}, year={2014}, collection={Nat. Commun.} }'
  chicago: Versteegh, M.A.M, M.E  Reimer, Klaus D. Jöns, D Dalacu, P.J Poole, A  Gulinatti,
    A Giudice, and V Zwiller. “Observation of strongly entangled photon pairs from
    a nanowire quantum dot.” Nat. Commun., 2014.
  ieee: M. A. M.  Versteegh <i>et al.</i>, “Observation of strongly entangled photon
    pairs from a nanowire quantum dot,” vol. 5. 2014.
  mla: Versteegh, M. A. M., et al. <i>Observation of strongly entangled photon pairs
    from a nanowire quantum dot</i>. 5298, 2014.
  short: M.A.M.  Versteegh, M.E.  Reimer, K.D. Jöns, D. Dalacu, P.J. Poole, A.  Gulinatti,
    A. Giudice, V. Zwiller, 5 (2014).
date_created: 2023-02-13T07:47:06Z
date_updated: 2023-02-13T08:46:47Z
department:
- _id: '623'
intvolume: '         5'
language:
- iso: ger
publication_status: published
series_title: Nat. Commun.
status: public
title: Observation of strongly entangled photon pairs from a nanowire quantum dot
type: conference
user_id: '71124'
volume: 5
year: '2014'
...
---
_id: '42026'
author:
- first_name: M
  full_name: Müller, M
  last_name: Müller
- first_name: S
  full_name: Bounouar, S
  last_name: Bounouar
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: M
  full_name: ' Glässl, M'
  last_name: ' Glässl'
- first_name: P
  full_name: ' Michler, P'
  last_name: ' Michler'
citation:
  ama: Müller M, Bounouar S, Jöns KD,  Glässl M,  Michler P. On-demand generation
    of indistinguishable polarization-entangled photon pairs. 2014;8:224-228.
  apa: Müller, M., Bounouar, S., Jöns, K. D.,  Glässl, M., &#38;  Michler, P. (2014).
    <i>On-demand generation of indistinguishable polarization-entangled photon pairs</i>
    (Vol. 8, pp. 224–228).
  bibtex: '@article{Müller_Bounouar_Jöns_ Glässl_ Michler_2014, series={Nat. Photon.},
    title={On-demand generation of indistinguishable polarization-entangled photon
    pairs}, volume={8}, author={Müller, M and Bounouar, S and Jöns, Klaus D. and  Glässl,
    M and  Michler, P}, year={2014}, pages={224–228}, collection={Nat. Photon.} }'
  chicago: Müller, M, S Bounouar, Klaus D. Jöns, M  Glässl, and P  Michler. “On-Demand
    Generation of Indistinguishable Polarization-Entangled Photon Pairs.” Nat. Photon.,
    2014.
  ieee: M. Müller, S. Bounouar, K. D. Jöns, M.  Glässl, and P.  Michler, “On-demand
    generation of indistinguishable polarization-entangled photon pairs,” vol. 8.
    pp. 224–228, 2014.
  mla: Müller, M., et al. <i>On-Demand Generation of Indistinguishable Polarization-Entangled
    Photon Pairs</i>. 2014, pp. 224–28.
  short: M. Müller, S. Bounouar, K.D. Jöns, M.  Glässl, P.  Michler, 8 (2014) 224–228.
date_created: 2023-02-13T07:57:50Z
date_updated: 2023-02-13T12:31:45Z
department:
- _id: '623'
intvolume: '         8'
language:
- iso: eng
page: 224-228
series_title: Nat. Photon.
status: public
title: On-demand generation of indistinguishable polarization-entangled photon pairs
type: conference
user_id: '71124'
volume: 8
year: '2014'
...
---
_id: '8171'
abstract:
- lang: eng
  text: "The polynomial hierarchy plays a central role in classical complexity theory.
    Here, we define\r\na quantum generalization of the polynomial hierarchy, and initiate
    its study. We show that\r\nnot only are there natural complete problems for the
    second level of this quantum hierarchy, but that these problems are in fact hard
    to approximate. Using the same techniques, we\r\nalso obtain hardness of approximation
    for the class QCMA. Our approach is based on the\r\nuse of dispersers, and is
    inspired by the classical results of Umans regarding hardness of approximation
    for the second level of the classical polynomial hierarchy [Umans, FOCS 1999].\r\nThe
    problems for which we prove hardness of approximation for include, among others,
    a\r\nquantum version of the Succinct Set Cover problem, and a variant of the local
    Hamiltonian\r\nproblem with hybrid classical-quantum ground states."
article_type: original
author:
- first_name: Sevag
  full_name: Gharibian, Sevag
  id: '71541'
  last_name: Gharibian
  orcid: 0000-0002-9992-3379
- first_name: Julia
  full_name: Kempe, Julia
  last_name: Kempe
citation:
  ama: Gharibian S, Kempe J. Hardness of approximation for quantum problems. <i>Quantum
    Information &#38; Computation</i>. 2014;14(5-6):517-540.
  apa: Gharibian, S., &#38; Kempe, J. (2014). Hardness of approximation for quantum
    problems. <i>Quantum Information &#38; Computation</i>, <i>14</i>(5–6), 517–540.
  bibtex: '@article{Gharibian_Kempe_2014, title={Hardness of approximation for quantum
    problems}, volume={14}, number={5–6}, journal={Quantum Information &#38; Computation},
    author={Gharibian, Sevag and Kempe, Julia}, year={2014}, pages={517–540} }'
  chicago: 'Gharibian, Sevag, and Julia Kempe. “Hardness of Approximation for Quantum
    Problems.” <i>Quantum Information &#38; Computation</i> 14, no. 5–6 (2014): 517–40.'
  ieee: S. Gharibian and J. Kempe, “Hardness of approximation for quantum problems,”
    <i>Quantum Information &#38; Computation</i>, vol. 14, no. 5–6, pp. 517–540, 2014.
  mla: Gharibian, Sevag, and Julia Kempe. “Hardness of Approximation for Quantum Problems.”
    <i>Quantum Information &#38; Computation</i>, vol. 14, no. 5–6, 2014, pp. 517–40.
  short: S. Gharibian, J. Kempe, Quantum Information &#38; Computation 14 (2014) 517–540.
date_created: 2019-03-01T11:56:55Z
date_updated: 2023-02-28T11:02:47Z
department:
- _id: '623'
- _id: '7'
extern: '1'
external_id:
  arxiv:
  - '1209.1055'
intvolume: '        14'
issue: 5-6
keyword:
- Hardness of approximation
- polynomial time hierarchy
- succinct set cover
- quantum complexity
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1209.1055
oa: '1'
page: 517-540
publication: Quantum Information & Computation
publication_status: published
status: public
title: Hardness of approximation for quantum problems
type: journal_article
user_id: '71541'
volume: 14
year: '2014'
...
---
_id: '8172'
abstract:
- lang: eng
  text: We show how to efficiently simulate continuous-time quantum query algorithms
    that run in time T in a manner that preserves the query complexity (within a polylogarithmic
    factor) while also incurring a small overhead cost in the total number of gates
    between queries. By small overhead, we mean T within a factor that is polylogarithmic
    in terms of T and a cost measure that reflects the cost of computing the driving
    Hamiltonian. This permits any continuous-time quantum algorithm based on an efficiently
    computable driving Hamiltonian to be converted into a gate-efficient algorithm
    with similar running time.
article_type: original
author:
- first_name: Dominic
  full_name: W. Berry, Dominic
  last_name: W. Berry
- first_name: Richard
  full_name: Cleve, Richard
  last_name: Cleve
- first_name: Sevag
  full_name: Gharibian, Sevag
  id: '71541'
  last_name: Gharibian
  orcid: 0000-0002-9992-3379
citation:
  ama: W. Berry D, Cleve R, Gharibian S. Gate-efficient discrete simulations of continuous-time
    quantum query algorithms. <i>Quantum Information &#38; Computation</i>. 2014;14(1-2):1-30.
  apa: W. Berry, D., Cleve, R., &#38; Gharibian, S. (2014). Gate-efficient discrete
    simulations of continuous-time quantum query algorithms. <i>Quantum Information
    &#38; Computation</i>, <i>14</i>(1–2), 1–30.
  bibtex: '@article{W. Berry_Cleve_Gharibian_2014, title={Gate-efficient discrete
    simulations of continuous-time quantum query algorithms}, volume={14}, number={1–2},
    journal={Quantum Information &#38; Computation}, author={W. Berry, Dominic and
    Cleve, Richard and Gharibian, Sevag}, year={2014}, pages={1–30} }'
  chicago: 'W. Berry, Dominic, Richard Cleve, and Sevag Gharibian. “Gate-Efficient
    Discrete Simulations of Continuous-Time Quantum Query Algorithms.” <i>Quantum
    Information &#38; Computation</i> 14, no. 1–2 (2014): 1–30.'
  ieee: D. W. Berry, R. Cleve, and S. Gharibian, “Gate-efficient discrete simulations
    of continuous-time quantum query algorithms,” <i>Quantum Information &#38; Computation</i>,
    vol. 14, no. 1–2, pp. 1–30, 2014.
  mla: W. Berry, Dominic, et al. “Gate-Efficient Discrete Simulations of Continuous-Time
    Quantum Query Algorithms.” <i>Quantum Information &#38; Computation</i>, vol.
    14, no. 1–2, 2014, pp. 1–30.
  short: D. W. Berry, R. Cleve, S. Gharibian, Quantum Information &#38; Computation
    14 (2014) 1–30.
date_created: 2019-03-01T11:59:24Z
date_updated: 2023-02-28T11:02:58Z
department:
- _id: '623'
- _id: '7'
extern: '1'
external_id:
  arxiv:
  - '1211.4637'
intvolume: '        14'
issue: 1-2
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1211.4637
oa: '1'
page: 1-30
publication: Quantum Information & Computation
publication_status: published
status: public
title: Gate-efficient discrete simulations of continuous-time quantum query algorithms
type: journal_article
user_id: '71541'
volume: 14
year: '2014'
...
---
_id: '42027'
author:
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: P.
  full_name: ' Atkinson, P.'
  last_name: ' Atkinson'
- first_name: M.
  full_name: Müller, M.
  last_name: Müller
- first_name: M.
  full_name: Heldmaier, M.
  last_name: Heldmaier
- first_name: S. M.
  full_name: Ulrich, S. M.
  last_name: Ulrich
- first_name: O. G.
  full_name: Schmidt, O. G.
  last_name: Schmidt
- first_name: P.
  full_name: Michler, P.
  last_name: Michler
citation:
  ama: Jöns KD,  Atkinson P, Müller M, et al. Triggered Indistinguishable Single Photons
    with Narrow Line Widths from Site-Controlled Quantum Dots. 2013;13(1):126-130.
  apa: Jöns, K. D.,  Atkinson, P., Müller, M., Heldmaier, M., Ulrich, S. M., Schmidt,
    O. G., &#38; Michler, P. (2013). <i>Triggered Indistinguishable Single Photons
    with Narrow Line Widths from Site-Controlled Quantum Dots</i> (Vol. 13, Issue
    1, pp. 126–130).
  bibtex: '@article{Jöns_ Atkinson_Müller_Heldmaier_Ulrich_Schmidt_Michler_2013, series={Nano
    Lett. }, title={Triggered Indistinguishable Single Photons with Narrow Line Widths
    from Site-Controlled Quantum Dots}, volume={13}, number={1}, author={Jöns, Klaus
    D. and  Atkinson, P. and Müller, M. and Heldmaier, M. and Ulrich, S. M. and Schmidt,
    O. G. and Michler, P.}, year={2013}, pages={126–130}, collection={Nano Lett. }
    }'
  chicago: Jöns, Klaus D., P.  Atkinson, M. Müller, M. Heldmaier, S. M. Ulrich, O.
    G. Schmidt, and P. Michler. “Triggered Indistinguishable Single Photons with Narrow
    Line Widths from Site-Controlled Quantum Dots.” Nano Lett. , 2013.
  ieee: K. D. Jöns <i>et al.</i>, “Triggered Indistinguishable Single Photons with
    Narrow Line Widths from Site-Controlled Quantum Dots,” vol. 13, no. 1. pp. 126–130,
    2013.
  mla: Jöns, Klaus D., et al. <i>Triggered Indistinguishable Single Photons with Narrow
    Line Widths from Site-Controlled Quantum Dots</i>. no. 1, 2013, pp. 126–30.
  short: K.D. Jöns, P.  Atkinson, M. Müller, M. Heldmaier, S.M. Ulrich, O.G. Schmidt,
    P. Michler, 13 (2013) 126–130.
date_created: 2023-02-13T08:02:04Z
date_updated: 2023-02-13T12:30:09Z
department:
- _id: '623'
intvolume: '        13'
issue: '1'
language:
- iso: ger
page: 126-130
publication_status: published
series_title: 'Nano Lett. '
status: public
title: Triggered Indistinguishable Single Photons with Narrow Line Widths from Site-Controlled
  Quantum Dots
type: conference
user_id: '71124'
volume: 13
year: '2013'
...
---
_id: '8425'
abstract:
- lang: eng
  text: "This thesis studies three topics in quantum computation and information:
    The approximability of quantum problems, quantum proof systems, and non-classical
    correlations in quantum systems. \r\n\r\nIn the first area, we demonstrate a polynomial-time
    (classical) approximation algorithm for dense instances of the canonical QMA-complete
    quantum constraint satisfaction problem, the local Hamiltonian problem. In the
    opposite direction, we next introduce a quantum generalization of the polynomial-time
    hierarchy, and define problems which we prove are not only complete for the second
    level of this hierarchy, but are in fact hard to approximate. \r\n\r\nIn the second
    area, we study variants of the interesting and stubbornly open question of whether
    a quantum proof system with multiple unentangled quantum provers is equal in expressive
    power to a proof system with a single quantum prover. Our results concern classes
    such as BellQMA(poly), and include a novel proof of perfect parallel repetition
    for SepQMA(m) based on cone programming duality. \r\n\r\nIn the third area, we
    study non-classical quantum correlations beyond entanglement, often dubbed \"non-classicality\".
    Among our results are two novel schemes for quantifying non-classicality: The
    first proposes the new paradigm of exploiting local unitary operations to study
    non-classical correlations, and the second introduces a protocol through which
    non-classical correlations in a starting system can be \"activated\" into distillable
    entanglement with an ancilla system. \r\n\r\nAn introduction to all required linear
    algebra and quantum mechanics is included."
author:
- first_name: Sevag
  full_name: Gharibian, Sevag
  id: '71541'
  last_name: Gharibian
  orcid: 0000-0002-9992-3379
citation:
  ama: Gharibian S. <i>Approximation, Proof Systems, and Correlations in a Quantum
    World</i>.; 2013.
  apa: Gharibian, S. (2013). <i>Approximation, Proof Systems, and Correlations in
    a Quantum World</i>.
  bibtex: '@book{Gharibian_2013, title={Approximation, Proof Systems, and Correlations
    in a Quantum World}, author={Gharibian, Sevag}, year={2013} }'
  chicago: Gharibian, Sevag. <i>Approximation, Proof Systems, and Correlations in
    a Quantum World</i>, 2013.
  ieee: S. Gharibian, <i>Approximation, Proof Systems, and Correlations in a Quantum
    World</i>. 2013.
  mla: Gharibian, Sevag. <i>Approximation, Proof Systems, and Correlations in a Quantum
    World</i>. 2013.
  short: S. Gharibian, Approximation, Proof Systems, and Correlations in a Quantum
    World, 2013.
date_created: 2019-03-06T14:35:06Z
date_updated: 2023-02-28T11:00:15Z
department:
- _id: '623'
- _id: '7'
extern: '1'
external_id:
  arxiv:
  - '1301.2632'
language:
- iso: eng
main_file_link:
- open_access: '1'
oa: '1'
page: '240'
related_material:
  link:
  - relation: confirmation
    url: https://arxiv.org/abs/1301.2632
status: public
title: Approximation, Proof Systems, and Correlations in a Quantum World
type: dissertation
user_id: '71541'
year: '2013'
...
---
_id: '8173'
abstract:
- lang: eng
  text: We study three variants of multi-prover quantum Merlin-Arthur proof systems.
    We first show that the class of problems that can be efficiently verified using
    polynomially many quantum proofs, each of logarithmic-size, is exactly MQA (also
    known as QCMA), the class of problems which can be efficiently verified via a
    classical proof and a quantum verifier. We then study the class BellQMA(poly),
    characterized by a verifier who first applies unentangled, nonadaptive measurements
    to each of the polynomially many proofs, followed by an arbitrary but efficient
    quantum verification circuit on the resulting measurement outcomes. We show that
    if the number of outcomes per nonadaptive measurement is a polynomially-bounded
    function, then the expressive power of the proof system is exactly QMA. Finally,
    we study a class equivalent to QMA(m), denoted SepQMA(m), where the verifier's
    measurement operator corresponding to outcome "accept" is a fully separable operator
    across the m quantum proofs. Using cone programming duality, we give an alternate
    proof of a result of Harrow and Montanaro [FOCS, pp. 633--642 (2010)] that shows
    a perfect parallel repetition theorem for SepQMA(m) for any m.
article_type: original
author:
- first_name: Sevag
  full_name: Gharibian, Sevag
  id: '71541'
  last_name: Gharibian
  orcid: 0000-0002-9992-3379
- first_name: Jamie
  full_name: Sikora, Jamie
  last_name: Sikora
- first_name: Sarvagya
  full_name: Upadhyay, Sarvagya
  last_name: Upadhyay
citation:
  ama: Gharibian S, Sikora J, Upadhyay S. QMA variants with polynomially many provers.
    <i>Quantum Information &#38; Computation</i>. 2013;13(1-2):135-157.
  apa: Gharibian, S., Sikora, J., &#38; Upadhyay, S. (2013). QMA variants with polynomially
    many provers. <i>Quantum Information &#38; Computation</i>, <i>13</i>(1–2), 135–157.
  bibtex: '@article{Gharibian_Sikora_Upadhyay_2013, title={QMA variants with polynomially
    many provers}, volume={13}, number={1–2}, journal={Quantum Information &#38; Computation},
    author={Gharibian, Sevag and Sikora, Jamie and Upadhyay, Sarvagya}, year={2013},
    pages={135–157} }'
  chicago: 'Gharibian, Sevag, Jamie Sikora, and Sarvagya Upadhyay. “QMA Variants with
    Polynomially Many Provers.” <i>Quantum Information &#38; Computation</i> 13, no.
    1–2 (2013): 135–57.'
  ieee: S. Gharibian, J. Sikora, and S. Upadhyay, “QMA variants with polynomially
    many provers,” <i>Quantum Information &#38; Computation</i>, vol. 13, no. 1–2,
    pp. 135–157, 2013.
  mla: Gharibian, Sevag, et al. “QMA Variants with Polynomially Many Provers.” <i>Quantum
    Information &#38; Computation</i>, vol. 13, no. 1–2, 2013, pp. 135–57.
  short: S. Gharibian, J. Sikora, S. Upadhyay, Quantum Information &#38; Computation
    13 (2013) 135–157.
date_created: 2019-03-01T12:00:39Z
date_updated: 2023-02-28T11:03:13Z
department:
- _id: '623'
- _id: '7'
extern: '1'
external_id:
  arxiv:
  - '1108.0617'
intvolume: '        13'
issue: 1-2
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1108.0617
oa: '1'
page: 135-157
publication: Quantum Information & Computation
publication_status: published
status: public
title: QMA variants with polynomially many provers
type: journal_article
user_id: '71541'
volume: 13
year: '2013'
...
---
_id: '31300'
article_number: '066205'
author:
- first_name: A.
  full_name: Potzuweit, A.
  last_name: Potzuweit
- first_name: Tobias
  full_name: Weich, Tobias
  id: '49178'
  last_name: Weich
  orcid: 0000-0002-9648-6919
- first_name: Sonja
  full_name: Barkhofen, Sonja
  id: '48188'
  last_name: Barkhofen
- first_name: U.
  full_name: Kuhl, U.
  last_name: Kuhl
- first_name: H.-J.
  full_name: Stöckmann, H.-J.
  last_name: Stöckmann
- first_name: M.
  full_name: Zworski, M.
  last_name: Zworski
citation:
  ama: 'Potzuweit A, Weich T, Barkhofen S, Kuhl U, Stöckmann H-J, Zworski M. Weyl
    asymptotics: From closed to open systems. <i>Physical Review E</i>. 2012;86(6).
    doi:<a href="https://doi.org/10.1103/physreve.86.066205">10.1103/physreve.86.066205</a>'
  apa: 'Potzuweit, A., Weich, T., Barkhofen, S., Kuhl, U., Stöckmann, H.-J., &#38;
    Zworski, M. (2012). Weyl asymptotics: From closed to open systems. <i>Physical
    Review E</i>, <i>86</i>(6), Article 066205. <a href="https://doi.org/10.1103/physreve.86.066205">https://doi.org/10.1103/physreve.86.066205</a>'
  bibtex: '@article{Potzuweit_Weich_Barkhofen_Kuhl_Stöckmann_Zworski_2012, title={Weyl
    asymptotics: From closed to open systems}, volume={86}, DOI={<a href="https://doi.org/10.1103/physreve.86.066205">10.1103/physreve.86.066205</a>},
    number={6066205}, journal={Physical Review E}, publisher={American Physical Society
    (APS)}, author={Potzuweit, A. and Weich, Tobias and Barkhofen, Sonja and Kuhl,
    U. and Stöckmann, H.-J. and Zworski, M.}, year={2012} }'
  chicago: 'Potzuweit, A., Tobias Weich, Sonja Barkhofen, U. Kuhl, H.-J. Stöckmann,
    and M. Zworski. “Weyl Asymptotics: From Closed to Open Systems.” <i>Physical Review
    E</i> 86, no. 6 (2012). <a href="https://doi.org/10.1103/physreve.86.066205">https://doi.org/10.1103/physreve.86.066205</a>.'
  ieee: 'A. Potzuweit, T. Weich, S. Barkhofen, U. Kuhl, H.-J. Stöckmann, and M. Zworski,
    “Weyl asymptotics: From closed to open systems,” <i>Physical Review E</i>, vol.
    86, no. 6, Art. no. 066205, 2012, doi: <a href="https://doi.org/10.1103/physreve.86.066205">10.1103/physreve.86.066205</a>.'
  mla: 'Potzuweit, A., et al. “Weyl Asymptotics: From Closed to Open Systems.” <i>Physical
    Review E</i>, vol. 86, no. 6, 066205, American Physical Society (APS), 2012, doi:<a
    href="https://doi.org/10.1103/physreve.86.066205">10.1103/physreve.86.066205</a>.'
  short: A. Potzuweit, T. Weich, S. Barkhofen, U. Kuhl, H.-J. Stöckmann, M. Zworski,
    Physical Review E 86 (2012).
date_created: 2022-05-17T13:01:39Z
date_updated: 2022-05-19T10:18:57Z
department:
- _id: '10'
- _id: '623'
- _id: '548'
doi: 10.1103/physreve.86.066205
external_id:
  arxiv:
  - '1209.2304'
intvolume: '        86'
issue: '6'
keyword:
- Industrial and Manufacturing Engineering
- Metals and Alloys
- Strategy and Management
- Mechanical Engineering
language:
- iso: eng
publication: Physical Review E
publication_identifier:
  issn:
  - 1539-3755
  - 1550-2376
publication_status: published
publisher: American Physical Society (APS)
status: public
title: 'Weyl asymptotics: From closed to open systems'
type: journal_article
user_id: '49178'
volume: 86
year: '2012'
...
---
_id: '40165'
article_number: '27388'
author:
- first_name: Dror
  full_name: Shayovitz, Dror
  last_name: Shayovitz
- first_name: Harald
  full_name: Herrmann, Harald
  id: '216'
  last_name: Herrmann
- first_name: Wolfgang
  full_name: Sohler, Wolfgang
  last_name: Sohler
- first_name: Raimund
  full_name: Ricken, Raimund
  last_name: Ricken
- first_name: Christine
  full_name: Silberhorn, Christine
  id: '26263'
  last_name: Silberhorn
- first_name: Dan M.
  full_name: Marom, Dan M.
  last_name: Marom
citation:
  ama: Shayovitz D, Herrmann H, Sohler W, Ricken R, Silberhorn C, Marom DM. High resolution
    time-to-space conversion of sub-picosecond pulses at 155µm by non-degenerate SFG
    in PPLN crystal. <i>Optics Express</i>. 2012;20(24). doi:<a href="https://doi.org/10.1364/oe.20.027388">10.1364/oe.20.027388</a>
  apa: Shayovitz, D., Herrmann, H., Sohler, W., Ricken, R., Silberhorn, C., &#38;
    Marom, D. M. (2012). High resolution time-to-space conversion of sub-picosecond
    pulses at 155µm by non-degenerate SFG in PPLN crystal. <i>Optics Express</i>,
    <i>20</i>(24), Article 27388. <a href="https://doi.org/10.1364/oe.20.027388">https://doi.org/10.1364/oe.20.027388</a>
  bibtex: '@article{Shayovitz_Herrmann_Sohler_Ricken_Silberhorn_Marom_2012, title={High
    resolution time-to-space conversion of sub-picosecond pulses at 155µm by non-degenerate
    SFG in PPLN crystal}, volume={20}, DOI={<a href="https://doi.org/10.1364/oe.20.027388">10.1364/oe.20.027388</a>},
    number={2427388}, journal={Optics Express}, publisher={The Optical Society}, author={Shayovitz,
    Dror and Herrmann, Harald and Sohler, Wolfgang and Ricken, Raimund and Silberhorn,
    Christine and Marom, Dan M.}, year={2012} }'
  chicago: Shayovitz, Dror, Harald Herrmann, Wolfgang Sohler, Raimund Ricken, Christine
    Silberhorn, and Dan M. Marom. “High Resolution Time-to-Space Conversion of Sub-Picosecond
    Pulses at 155µm by Non-Degenerate SFG in PPLN Crystal.” <i>Optics Express</i>
    20, no. 24 (2012). <a href="https://doi.org/10.1364/oe.20.027388">https://doi.org/10.1364/oe.20.027388</a>.
  ieee: 'D. Shayovitz, H. Herrmann, W. Sohler, R. Ricken, C. Silberhorn, and D. M.
    Marom, “High resolution time-to-space conversion of sub-picosecond pulses at 155µm
    by non-degenerate SFG in PPLN crystal,” <i>Optics Express</i>, vol. 20, no. 24,
    Art. no. 27388, 2012, doi: <a href="https://doi.org/10.1364/oe.20.027388">10.1364/oe.20.027388</a>.'
  mla: Shayovitz, Dror, et al. “High Resolution Time-to-Space Conversion of Sub-Picosecond
    Pulses at 155µm by Non-Degenerate SFG in PPLN Crystal.” <i>Optics Express</i>,
    vol. 20, no. 24, 27388, The Optical Society, 2012, doi:<a href="https://doi.org/10.1364/oe.20.027388">10.1364/oe.20.027388</a>.
  short: D. Shayovitz, H. Herrmann, W. Sohler, R. Ricken, C. Silberhorn, D.M. Marom,
    Optics Express 20 (2012).
date_created: 2023-01-26T07:45:34Z
date_updated: 2023-01-30T12:45:02Z
department:
- _id: '288'
- _id: '15'
- _id: '623'
- _id: '230'
doi: 10.1364/oe.20.027388
intvolume: '        20'
issue: '24'
keyword:
- Atomic and Molecular Physics
- and Optics
language:
- iso: eng
publication: Optics Express
publication_identifier:
  issn:
  - 1094-4087
publication_status: published
publisher: The Optical Society
status: public
title: High resolution time-to-space conversion of sub-picosecond pulses at 155µm
  by non-degenerate SFG in PPLN crystal
type: journal_article
user_id: '26263'
volume: 20
year: '2012'
...
---
_id: '40167'
article_number: '105011'
author:
- first_name: Kaisa
  full_name: Laiho, Kaisa
  last_name: Laiho
- first_name: Malte
  full_name: Avenhaus, Malte
  last_name: Avenhaus
- first_name: Christine
  full_name: Silberhorn, Christine
  id: '26263'
  last_name: Silberhorn
citation:
  ama: Laiho K, Avenhaus M, Silberhorn C. Characteristics of displaced single photons
    attained via higher order factorial moments. <i>New Journal of Physics</i>. 2012;14(10).
    doi:<a href="https://doi.org/10.1088/1367-2630/14/10/105011">10.1088/1367-2630/14/10/105011</a>
  apa: Laiho, K., Avenhaus, M., &#38; Silberhorn, C. (2012). Characteristics of displaced
    single photons attained via higher order factorial moments. <i>New Journal of
    Physics</i>, <i>14</i>(10), Article 105011. <a href="https://doi.org/10.1088/1367-2630/14/10/105011">https://doi.org/10.1088/1367-2630/14/10/105011</a>
  bibtex: '@article{Laiho_Avenhaus_Silberhorn_2012, title={Characteristics of displaced
    single photons attained via higher order factorial moments}, volume={14}, DOI={<a
    href="https://doi.org/10.1088/1367-2630/14/10/105011">10.1088/1367-2630/14/10/105011</a>},
    number={10105011}, journal={New Journal of Physics}, publisher={IOP Publishing},
    author={Laiho, Kaisa and Avenhaus, Malte and Silberhorn, Christine}, year={2012}
    }'
  chicago: Laiho, Kaisa, Malte Avenhaus, and Christine Silberhorn. “Characteristics
    of Displaced Single Photons Attained via Higher Order Factorial Moments.” <i>New
    Journal of Physics</i> 14, no. 10 (2012). <a href="https://doi.org/10.1088/1367-2630/14/10/105011">https://doi.org/10.1088/1367-2630/14/10/105011</a>.
  ieee: 'K. Laiho, M. Avenhaus, and C. Silberhorn, “Characteristics of displaced single
    photons attained via higher order factorial moments,” <i>New Journal of Physics</i>,
    vol. 14, no. 10, Art. no. 105011, 2012, doi: <a href="https://doi.org/10.1088/1367-2630/14/10/105011">10.1088/1367-2630/14/10/105011</a>.'
  mla: Laiho, Kaisa, et al. “Characteristics of Displaced Single Photons Attained
    via Higher Order Factorial Moments.” <i>New Journal of Physics</i>, vol. 14, no.
    10, 105011, IOP Publishing, 2012, doi:<a href="https://doi.org/10.1088/1367-2630/14/10/105011">10.1088/1367-2630/14/10/105011</a>.
  short: K. Laiho, M. Avenhaus, C. Silberhorn, New Journal of Physics 14 (2012).
date_created: 2023-01-26T07:48:21Z
date_updated: 2023-01-30T12:45:38Z
department:
- _id: '288'
- _id: '15'
- _id: '623'
- _id: '230'
doi: 10.1088/1367-2630/14/10/105011
intvolume: '        14'
issue: '10'
keyword:
- General Physics and Astronomy
language:
- iso: eng
publication: New Journal of Physics
publication_identifier:
  issn:
  - 1367-2630
publication_status: published
publisher: IOP Publishing
status: public
title: Characteristics of displaced single photons attained via higher order factorial
  moments
type: journal_article
user_id: '26263'
volume: 14
year: '2012'
...
---
_id: '42033'
author:
- first_name: A
  full_name: Rastelli, A
  last_name: Rastelli
- first_name: F
  full_name: Ding, F
  last_name: Ding
- first_name: J.D
  full_name: Plumhof, J.D
  last_name: Plumhof
- first_name: S
  full_name: Kumar, S
  last_name: Kumar
- first_name: R
  full_name: Trotta, R
  last_name: Trotta
- first_name: C
  full_name: Deneke, C
  last_name: Deneke
- first_name: A
  full_name: ' Malachias, A'
  last_name: ' Malachias'
- first_name: P
  full_name: Atkinson, P
  last_name: Atkinson
- first_name: E
  full_name: Zallo, E
  last_name: Zallo
- first_name: T
  full_name: Zander, T
  last_name: Zander
- first_name: A
  full_name: Herklotz, A
  last_name: Herklotz
- first_name: R
  full_name: ' Singh, R'
  last_name: ' Singh'
- first_name: V
  full_name: Krápek, V
  last_name: Krápek
- first_name: J.R
  full_name: Schrötel, J.R
  last_name: Schrötel
- first_name: S
  full_name: ' Kiravittaya, S'
  last_name: ' Kiravittaya'
- first_name: M
  full_name: Benyoucef,, M
  last_name: Benyoucef,
- first_name: R
  full_name: Hafenbrak, R
  last_name: Hafenbrak
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: D.J
  full_name: Thurmer, D.J
  last_name: Thurmer
- first_name: D
  full_name: Grimm, D
  last_name: Grimm
- first_name: G
  full_name: ' Bester, G'
  last_name: ' Bester'
- first_name: K
  full_name: Dörr, K
  last_name: Dörr
- first_name: P
  full_name: Michler, P
  last_name: Michler
- first_name: O.G
  full_name: Schmidt, O.G
  last_name: Schmidt
citation:
  ama: Rastelli A, Ding F, Plumhof JD, et al. Controlling quantum dot emission by
    integration of semiconductor nanomembranes onto piezoelectric actuators. 2012;249(4):687-696.
  apa: Rastelli, A., Ding, F., Plumhof, J. D., Kumar, S., Trotta, R., Deneke, C.,  Malachias,
    A., Atkinson, P., Zallo, E., Zander, T., Herklotz, A.,  Singh, R., Krápek, V.,
    Schrötel, J. R.,  Kiravittaya, S., Benyoucef, M., Hafenbrak, R., Jöns, K. D.,
    Thurmer, D. J., … Schmidt, O. G. (2012). <i>Controlling quantum dot emission by
    integration of semiconductor nanomembranes onto piezoelectric actuators</i> (Vol.
    249, Issue 4, pp. 687–696).
  bibtex: '@article{Rastelli_Ding_Plumhof_Kumar_Trotta_Deneke_ Malachias_Atkinson_Zallo_Zander_et
    al._2012, series={Phys. Status Solidi B }, title={Controlling quantum dot emission
    by integration of semiconductor nanomembranes onto piezoelectric actuators}, volume={249},
    number={4}, author={Rastelli, A and Ding, F and Plumhof, J.D and Kumar, S and
    Trotta, R and Deneke, C and  Malachias, A and Atkinson, P and Zallo, E and Zander,
    T and et al.}, year={2012}, pages={687–696}, collection={Phys. Status Solidi B
    } }'
  chicago: Rastelli, A, F Ding, J.D Plumhof, S Kumar, R Trotta, C Deneke, A  Malachias,
    et al. “Controlling Quantum Dot Emission by Integration of Semiconductor Nanomembranes
    onto Piezoelectric Actuators.” Phys. Status Solidi B , 2012.
  ieee: A. Rastelli <i>et al.</i>, “Controlling quantum dot emission by integration
    of semiconductor nanomembranes onto piezoelectric actuators,” vol. 249, no. 4.
    pp. 687–696, 2012.
  mla: Rastelli, A., et al. <i>Controlling Quantum Dot Emission by Integration of
    Semiconductor Nanomembranes onto Piezoelectric Actuators</i>. no. 4, 2012, pp.
    687–96.
  short: A. Rastelli, F. Ding, J.D. Plumhof, S. Kumar, R. Trotta, C. Deneke, A.  Malachias,
    P. Atkinson, E. Zallo, T. Zander, A. Herklotz, R.  Singh, V. Krápek, J.R. Schrötel,
    S.  Kiravittaya, M. Benyoucef, R. Hafenbrak, K.D. Jöns, D.J. Thurmer, D. Grimm,
    G.  Bester, K. Dörr, P. Michler, O.G. Schmidt, 249 (2012) 687–696.
date_created: 2023-02-13T08:44:08Z
date_updated: 2023-02-13T08:44:28Z
department:
- _id: '623'
intvolume: '       249'
issue: '4'
language:
- iso: eng
page: 687-696
series_title: 'Phys. Status Solidi B '
status: public
title: Controlling quantum dot emission by integration of semiconductor nanomembranes
  onto piezoelectric actuators
type: conference
user_id: '71124'
volume: 249
year: '2012'
...
---
_id: '42028'
article_number: '063526'
author:
- first_name: C
  full_name: Hermannstädter, C
  last_name: Hermannstädter
- first_name: M
  full_name: ' Witzany, M'
  last_name: ' Witzany'
- first_name: M
  full_name: Heldmaier, M
  last_name: Heldmaier
- first_name: R
  full_name: Hafenbrak, R
  last_name: Hafenbrak
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: G.J
  full_name: Beirne, G.J
  last_name: Beirne
- first_name: P
  full_name: Michler, P
  last_name: Michler
citation:
  ama: Hermannstädter C,  Witzany M, Heldmaier M, et al. Polarization anisotropic
    luminescence of tunable single lateral quantum dot molecules. 2012;111.
  apa: Hermannstädter, C.,  Witzany, M., Heldmaier, M., Hafenbrak, R., Jöns, K. D.,
    Beirne, G. J., &#38; Michler, P. (2012). <i>Polarization anisotropic luminescence
    of tunable single lateral quantum dot molecules</i> (No. 063526; Vol. 111).
  bibtex: '@article{Hermannstädter_ Witzany_Heldmaier_Hafenbrak_Jöns_Beirne_Michler_2012,
    series={Journal of Applied Physics }, title={Polarization anisotropic luminescence
    of tunable single lateral quantum dot molecules}, volume={111}, number={063526},
    author={Hermannstädter, C and  Witzany, M and Heldmaier, M and Hafenbrak, R and
    Jöns, Klaus D. and Beirne, G.J and Michler, P}, year={2012}, collection={Journal
    of Applied Physics } }'
  chicago: Hermannstädter, C, M  Witzany, M Heldmaier, R Hafenbrak, Klaus D. Jöns,
    G.J Beirne, and P Michler. “Polarization anisotropic luminescence of tunable single
    lateral quantum dot molecules.” Journal of Applied Physics , 2012.
  ieee: C. Hermannstädter <i>et al.</i>, “Polarization anisotropic luminescence of
    tunable single lateral quantum dot molecules,” vol. 111. 2012.
  mla: Hermannstädter, C., et al. <i>Polarization anisotropic luminescence of tunable
    single lateral quantum dot molecules</i>. 063526, 2012.
  short: C. Hermannstädter, M.  Witzany, M. Heldmaier, R. Hafenbrak, K.D. Jöns, G.J.
    Beirne, P. Michler, 111 (2012).
date_created: 2023-02-13T08:06:58Z
date_updated: 2023-02-13T08:45:12Z
department:
- _id: '623'
intvolume: '       111'
language:
- iso: ger
publication_status: published
series_title: 'Journal of Applied Physics '
status: public
title: Polarization anisotropic luminescence of tunable single lateral quantum dot
  molecules
type: conference
user_id: '71124'
volume: 111
year: '2012'
...
---
_id: '42029'
author:
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: R
  full_name: Hafenbrak, R
  last_name: Hafenbrak
- first_name: P
  full_name: Atkinson, P
  last_name: Atkinson
- first_name: A
  full_name: Rastelli, A
  last_name: Rastelli
- first_name: O.G
  full_name: Schmidt, O.G
  last_name: Schmidt
- first_name: P
  full_name: Michler, P
  last_name: Michler
citation:
  ama: Jöns KD, Hafenbrak R, Atkinson P, Rastelli A, Schmidt OG, Michler P. Quantum
    state tomography measurements on strain-tuned In(x)Ga(1−x)As/GaAs quantum dots.
    2012;249(4):697-701.
  apa: Jöns, K. D., Hafenbrak, R., Atkinson, P., Rastelli, A., Schmidt, O. G., &#38;
    Michler, P. (2012). <i>Quantum state tomography measurements on strain-tuned In(x)Ga(1−x)As/GaAs
    quantum dots</i> (Vol. 249, Issue 4, pp. 697–701).
  bibtex: '@article{Jöns_Hafenbrak_Atkinson_Rastelli_Schmidt_Michler_2012, series={Phys.
    Status Solidi B }, title={Quantum state tomography measurements on strain-tuned
    In(x)Ga(1−x)As/GaAs quantum dots}, volume={249}, number={4}, author={Jöns, Klaus
    D. and Hafenbrak, R and Atkinson, P and Rastelli, A and Schmidt, O.G and Michler,
    P}, year={2012}, pages={697–701}, collection={Phys. Status Solidi B } }'
  chicago: Jöns, Klaus D., R Hafenbrak, P Atkinson, A Rastelli, O.G Schmidt, and P
    Michler. “Quantum State Tomography Measurements on Strain-Tuned In(x)Ga(1−x)As/GaAs
    Quantum Dots.” Phys. Status Solidi B , 2012.
  ieee: K. D. Jöns, R. Hafenbrak, P. Atkinson, A. Rastelli, O. G. Schmidt, and P.
    Michler, “Quantum state tomography measurements on strain-tuned In(x)Ga(1−x)As/GaAs
    quantum dots,” vol. 249, no. 4. pp. 697–701, 2012.
  mla: Jöns, Klaus D., et al. <i>Quantum State Tomography Measurements on Strain-Tuned
    In(x)Ga(1−x)As/GaAs Quantum Dots</i>. no. 4, 2012, pp. 697–701.
  short: K.D. Jöns, R. Hafenbrak, P. Atkinson, A. Rastelli, O.G. Schmidt, P. Michler,
    249 (2012) 697–701.
date_created: 2023-02-13T08:13:12Z
date_updated: 2023-02-13T08:44:41Z
department:
- _id: '623'
intvolume: '       249'
issue: '4'
language:
- iso: eng
page: 697-701
series_title: 'Phys. Status Solidi B '
status: public
title: Quantum state tomography measurements on strain-tuned In(x)Ga(1−x)As/GaAs quantum
  dots
type: conference
user_id: '71124'
volume: 249
year: '2012'
...
---
_id: '8169'
abstract:
- lang: eng
  text: The polynomial hierarchy plays a central role in classical complexity theory.
    Here, we define a quantum generalization of the polynomial hierarchy, and initiate
    its study. We show that not only are there natural complete problems for the second
    level of this quantum hierarchy, but that these problems are in fact hard to approximate.
    Our work thus yields the first known hardness of approximation results for a quantum
    complexity class. Using these techniques, we also obtain hardness of approximation
    for the class QCMA. Our approach is based on the use of dispersers, and is inspired
    by the classical results of Umans regarding hardness of approximation for the
    second level of the classical polynomial hierarchy (Umans 1999). We close by showing
    that a variant of the local Hamiltonian problem with hybrid classical-quantum
    ground states is complete for the second level of our quantum hierarchy.
author:
- first_name: Sevag
  full_name: Gharibian, Sevag
  id: '71541'
  last_name: Gharibian
  orcid: 0000-0002-9992-3379
- first_name: Julia
  full_name: Kempe, Julia
  last_name: Kempe
citation:
  ama: 'Gharibian S, Kempe J. Hardness of Approximation for Quantum Problems. In:
    Czumaj A, Mehlhorn K, Pitts A, Wattenhofer R, eds. <i>International Colloquium
    on Automata, Languages, and Programming (ICALP 2012)</i>. Springer Berlin Heidelberg;
    2012:387-398. doi:<a href="https://doi.org/10.1007/978-3-642-31594-7_33">10.1007/978-3-642-31594-7_33</a>'
  apa: Gharibian, S., &#38; Kempe, J. (2012). Hardness of Approximation for Quantum
    Problems. In A. Czumaj, K. Mehlhorn, A. Pitts, &#38; R. Wattenhofer (Eds.), <i>International
    Colloquium on Automata, Languages, and Programming (ICALP 2012)</i> (pp. 387–398).
    Springer Berlin Heidelberg. <a href="https://doi.org/10.1007/978-3-642-31594-7_33">https://doi.org/10.1007/978-3-642-31594-7_33</a>
  bibtex: '@inproceedings{Gharibian_Kempe_2012, place={Berlin, Heidelberg}, title={Hardness
    of Approximation for Quantum Problems}, DOI={<a href="https://doi.org/10.1007/978-3-642-31594-7_33">10.1007/978-3-642-31594-7_33</a>},
    booktitle={International Colloquium on Automata, Languages, and Programming (ICALP
    2012)}, publisher={Springer Berlin Heidelberg}, author={Gharibian, Sevag and Kempe,
    Julia}, editor={Czumaj, Artur and Mehlhorn, Kurt and Pitts, Andrew and Wattenhofer,
    Roger}, year={2012}, pages={387–398} }'
  chicago: 'Gharibian, Sevag, and Julia Kempe. “Hardness of Approximation for Quantum
    Problems.” In <i>International Colloquium on Automata, Languages, and Programming
    (ICALP 2012)</i>, edited by Artur Czumaj, Kurt Mehlhorn, Andrew Pitts, and Roger
    Wattenhofer, 387–98. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. <a
    href="https://doi.org/10.1007/978-3-642-31594-7_33">https://doi.org/10.1007/978-3-642-31594-7_33</a>.'
  ieee: 'S. Gharibian and J. Kempe, “Hardness of Approximation for Quantum Problems,”
    in <i>International Colloquium on Automata, Languages, and Programming (ICALP
    2012)</i>, Warwick, UK, 2012, pp. 387–398, doi: <a href="https://doi.org/10.1007/978-3-642-31594-7_33">10.1007/978-3-642-31594-7_33</a>.'
  mla: Gharibian, Sevag, and Julia Kempe. “Hardness of Approximation for Quantum Problems.”
    <i>International Colloquium on Automata, Languages, and Programming (ICALP 2012)</i>,
    edited by Artur Czumaj et al., Springer Berlin Heidelberg, 2012, pp. 387–98, doi:<a
    href="https://doi.org/10.1007/978-3-642-31594-7_33">10.1007/978-3-642-31594-7_33</a>.
  short: 'S. Gharibian, J. Kempe, in: A. Czumaj, K. Mehlhorn, A. Pitts, R. Wattenhofer
    (Eds.), International Colloquium on Automata, Languages, and Programming (ICALP
    2012), Springer Berlin Heidelberg, Berlin, Heidelberg, 2012, pp. 387–398.'
conference:
  location: Warwick, UK
  name: International Colloquium on Automata, Languages, and Programming (ICALP)
date_created: 2019-03-01T11:55:18Z
date_updated: 2023-02-28T11:03:26Z
department:
- _id: '623'
- _id: '7'
doi: 10.1007/978-3-642-31594-7_33
editor:
- first_name: Artur
  full_name: Czumaj, Artur
  last_name: Czumaj
- first_name: Kurt
  full_name: Mehlhorn, Kurt
  last_name: Mehlhorn
- first_name: Andrew
  full_name: Pitts, Andrew
  last_name: Pitts
- first_name: Roger
  full_name: Wattenhofer, Roger
  last_name: Wattenhofer
extern: '1'
external_id:
  arxiv:
  - '1209.1055'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1209.1055
oa: '1'
page: 387-398
place: Berlin, Heidelberg
publication: International Colloquium on Automata, Languages, and Programming (ICALP
  2012)
publication_identifier:
  isbn:
  - 978-3-642-31594-7
publication_status: published
publisher: Springer Berlin Heidelberg
status: public
title: Hardness of Approximation for Quantum Problems
type: conference
user_id: '71541'
year: '2012'
...
---
_id: '8175'
abstract:
- lang: eng
  text: Approximation algorithms for classical constraint satisfaction problems are
    one of the main research areas in theoretical computer science. Here we define
    a natural approximation version of the QMA-complete local Hamiltonian problem
    (where QMA stands for Quantum Merlin Arthur) and initiate its study. We present
    two main results. The first shows that a nontrivial approximation ratio can be
    obtained in the class NP using product states. The second result (which builds
    on the first one) gives a polynomial time (classical) algorithm providing a similar
    approximation ratio for dense instances of the problem. The latter result is based
    on an adaptation of the “exhaustive sampling method” by Arora, Karger, and Karpinski
    [J. Comput. System Sci., 58 (1999), p. 193] to the quantum setting and might be
    of independent interest.
article_type: original
author:
- first_name: Sevag
  full_name: Gharibian, Sevag
  id: '71541'
  last_name: Gharibian
  orcid: 0000-0002-9992-3379
- first_name: Julia
  full_name: Kempe, Julia
  last_name: Kempe
citation:
  ama: Gharibian S, Kempe J. Approximation Algorithms for QMA-Complete Problems. <i>SIAM
    Journal on Computing</i>. 2012;41(4):1028-1050. doi:<a href="https://doi.org/10.1137/110842272">10.1137/110842272</a>
  apa: Gharibian, S., &#38; Kempe, J. (2012). Approximation Algorithms for QMA-Complete
    Problems. <i>SIAM Journal on Computing</i>, <i>41</i>(4), 1028–1050. <a href="https://doi.org/10.1137/110842272">https://doi.org/10.1137/110842272</a>
  bibtex: '@article{Gharibian_Kempe_2012, title={Approximation Algorithms for QMA-Complete
    Problems}, volume={41}, DOI={<a href="https://doi.org/10.1137/110842272">10.1137/110842272</a>},
    number={4}, journal={SIAM Journal on Computing}, publisher={Society for Industrial
    &#38; Applied Mathematics (SIAM)}, author={Gharibian, Sevag and Kempe, Julia},
    year={2012}, pages={1028–1050} }'
  chicago: 'Gharibian, Sevag, and Julia Kempe. “Approximation Algorithms for QMA-Complete
    Problems.” <i>SIAM Journal on Computing</i> 41, no. 4 (2012): 1028–50. <a href="https://doi.org/10.1137/110842272">https://doi.org/10.1137/110842272</a>.'
  ieee: 'S. Gharibian and J. Kempe, “Approximation Algorithms for QMA-Complete Problems,”
    <i>SIAM Journal on Computing</i>, vol. 41, no. 4, pp. 1028–1050, 2012, doi: <a
    href="https://doi.org/10.1137/110842272">10.1137/110842272</a>.'
  mla: Gharibian, Sevag, and Julia Kempe. “Approximation Algorithms for QMA-Complete
    Problems.” <i>SIAM Journal on Computing</i>, vol. 41, no. 4, Society for Industrial
    &#38; Applied Mathematics (SIAM), 2012, pp. 1028–50, doi:<a href="https://doi.org/10.1137/110842272">10.1137/110842272</a>.
  short: S. Gharibian, J. Kempe, SIAM Journal on Computing 41 (2012) 1028–1050.
date_created: 2019-03-01T12:04:03Z
date_updated: 2023-02-28T11:03:50Z
department:
- _id: '623'
- _id: '7'
doi: 10.1137/110842272
extern: '1'
external_id:
  arxiv:
  - '1101.3884'
intvolume: '        41'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1101.3884
oa: '1'
page: 1028-1050
publication: SIAM Journal on Computing
publication_identifier:
  issn:
  - 0097-5397
  - 1095-7111
publication_status: published
publisher: Society for Industrial & Applied Mathematics (SIAM)
status: public
title: Approximation Algorithms for QMA-Complete Problems
type: journal_article
user_id: '71541'
volume: 41
year: '2012'
...
---
_id: '8174'
abstract:
- lang: eng
  text: We propose a measure of non-classical correlations in bipartite quantum states
    based on local unitary operations. We prove the measure is non-zero if and only
    if the quantum discord is non-zero; this is achieved via a new characterization
    of zero discord states in terms of the state's correlation matrix. Moreover, our
    scheme can be extended to ensure the same relationship holds even with a generalized
    version of quantum discord in which higher-rank projective measurements are allowed.
    We next derive a closed form expression for our scheme in the cases of Werner
    states and (2 x N)-dimensional systems. The latter reveals that for (2 x N)-dimensional
    states, our measure reduces to the geometric discord [Dakic et al., PRL 105, 2010].
    A connection to the CHSH inequality is shown. We close with a characterization
    of all maximally non-classical, yet separable, (2 x N)-dimensional states of rank
    at most two (with respect to our measure).
article_type: original
author:
- first_name: Sevag
  full_name: Gharibian, Sevag
  id: '71541'
  last_name: Gharibian
  orcid: 0000-0002-9992-3379
citation:
  ama: Gharibian S. Quantifying nonclassicality with local unitary operations. <i>Physical
    Review A</i>. 2012;86:042106. doi:<a href="https://doi.org/10.1103/PhysRevA.86.042106">10.1103/PhysRevA.86.042106</a>
  apa: Gharibian, S. (2012). Quantifying nonclassicality with local unitary operations.
    <i>Physical Review A</i>, <i>86</i>, 042106. <a href="https://doi.org/10.1103/PhysRevA.86.042106">https://doi.org/10.1103/PhysRevA.86.042106</a>
  bibtex: '@article{Gharibian_2012, title={Quantifying nonclassicality with local
    unitary operations}, volume={86}, DOI={<a href="https://doi.org/10.1103/PhysRevA.86.042106">10.1103/PhysRevA.86.042106</a>},
    journal={Physical Review A}, publisher={American Physical Society}, author={Gharibian,
    Sevag}, year={2012}, pages={042106} }'
  chicago: 'Gharibian, Sevag. “Quantifying Nonclassicality with Local Unitary Operations.”
    <i>Physical Review A</i> 86 (2012): 042106. <a href="https://doi.org/10.1103/PhysRevA.86.042106">https://doi.org/10.1103/PhysRevA.86.042106</a>.'
  ieee: 'S. Gharibian, “Quantifying nonclassicality with local unitary operations,”
    <i>Physical Review A</i>, vol. 86, p. 042106, 2012, doi: <a href="https://doi.org/10.1103/PhysRevA.86.042106">10.1103/PhysRevA.86.042106</a>.'
  mla: Gharibian, Sevag. “Quantifying Nonclassicality with Local Unitary Operations.”
    <i>Physical Review A</i>, vol. 86, American Physical Society, 2012, p. 042106,
    doi:<a href="https://doi.org/10.1103/PhysRevA.86.042106">10.1103/PhysRevA.86.042106</a>.
  short: S. Gharibian, Physical Review A 86 (2012) 042106.
date_created: 2019-03-01T12:01:41Z
date_updated: 2023-02-28T11:03:38Z
department:
- _id: '623'
- _id: '7'
doi: 10.1103/PhysRevA.86.042106
extern: '1'
external_id:
  arxiv:
  - '1202.1598'
intvolume: '        86'
language:
- iso: eng
main_file_link:
- open_access: '1'
  url: https://arxiv.org/abs/1202.1598
oa: '1'
page: '042106'
publication: Physical Review A
publication_status: published
publisher: American Physical Society
status: public
title: Quantifying nonclassicality with local unitary operations
type: journal_article
user_id: '71541'
volume: 86
year: '2012'
...
---
_id: '42031'
article_number: '121302'
author:
- first_name: J.D
  full_name: Plumhof, J.D
  last_name: Plumhof
- first_name: V
  full_name: ' Krápek, V'
  last_name: ' Krápek'
- first_name: F
  full_name: Ding, F
  last_name: Ding
- first_name: Klaus D.
  full_name: Jöns, Klaus D.
  id: '85353'
  last_name: Jöns
- first_name: R
  full_name: Hafenbrak, R
  last_name: Hafenbrak
- first_name: P
  full_name: ' Klenovský, P'
  last_name: ' Klenovský'
- first_name: A
  full_name: Herklotz, A
  last_name: Herklotz
- first_name: K
  full_name: ' Dörr, K'
  last_name: ' Dörr'
- first_name: P
  full_name: ' Michler , P'
  last_name: ' Michler '
- first_name: A
  full_name: Rastelli,, A
  last_name: Rastelli,
- first_name: O.G
  full_name: Schmidt, O.G
  last_name: Schmidt
citation:
  ama: Plumhof JD,  Krápek V, Ding F, et al. Strain-induced anticrossing of bright
    exciton levels in single self-assembled GaAs/Al(x)Ga(1−x)As and In(x)Ga(1−x)As/GaAs
    quantum dots. 2011;83.
  apa: Plumhof, J. D.,  Krápek, V., Ding, F., Jöns, K. D., Hafenbrak, R.,  Klenovský,
    P., Herklotz, A.,  Dörr, K.,  Michler , P., Rastelli, A., &#38; Schmidt, O. G.
    (2011). <i>Strain-induced anticrossing of bright exciton levels in single self-assembled
    GaAs/Al(x)Ga(1−x)As and In(x)Ga(1−x)As/GaAs quantum dots</i> (No. 121302; Vol.
    83).
  bibtex: '@article{Plumhof_ Krápek_Ding_Jöns_Hafenbrak_ Klenovský_Herklotz_ Dörr_
    Michler _Rastelli,_et al._2011, series={Phys. Rev. B}, title={Strain-induced anticrossing
    of bright exciton levels in single self-assembled GaAs/Al(x)Ga(1−x)As and In(x)Ga(1−x)As/GaAs
    quantum dots}, volume={83}, number={121302}, author={Plumhof, J.D and  Krápek,
    V and Ding, F and Jöns, Klaus D. and Hafenbrak, R and  Klenovský, P and Herklotz,
    A and  Dörr, K and  Michler , P and Rastelli, A and et al.}, year={2011}, collection={Phys.
    Rev. B} }'
  chicago: Plumhof, J.D, V  Krápek, F Ding, Klaus D. Jöns, R Hafenbrak, P  Klenovský,
    A Herklotz, et al. “Strain-Induced Anticrossing of Bright Exciton Levels in Single
    Self-Assembled GaAs/Al(x)Ga(1−x)As and In(x)Ga(1−x)As/GaAs Quantum Dots.” Phys.
    Rev. B, 2011.
  ieee: J. D. Plumhof <i>et al.</i>, “Strain-induced anticrossing of bright exciton
    levels in single self-assembled GaAs/Al(x)Ga(1−x)As and In(x)Ga(1−x)As/GaAs quantum
    dots,” vol. 83. 2011.
  mla: Plumhof, J. D., et al. <i>Strain-Induced Anticrossing of Bright Exciton Levels
    in Single Self-Assembled GaAs/Al(x)Ga(1−x)As and In(x)Ga(1−x)As/GaAs Quantum Dots</i>.
    121302, 2011.
  short: J.D. Plumhof, V.  Krápek, F. Ding, K.D. Jöns, R. Hafenbrak, P.  Klenovský,
    A. Herklotz, K.  Dörr, P.  Michler , A. Rastelli,, O.G. Schmidt, 83 (2011).
date_created: 2023-02-13T08:26:54Z
date_updated: 2023-02-13T08:44:35Z
department:
- _id: '623'
intvolume: '        83'
language:
- iso: eng
series_title: Phys. Rev. B
status: public
title: Strain-induced anticrossing of bright exciton levels in single self-assembled
  GaAs/Al(x)Ga(1−x)As and In(x)Ga(1−x)As/GaAs quantum dots
type: conference
user_id: '71124'
volume: 83
year: '2011'
...
