@inproceedings{27531,
abstract = {{The Quantum Singular Value Transformation (QSVT) is a recent technique that
gives a unified framework to describe most quantum algorithms discovered so
far, and may lead to the development of novel quantum algorithms. In this paper
we investigate the hardness of classically simulating the QSVT. A recent result
by Chia, Gily\'en, Li, Lin, Tang and Wang (STOC 2020) showed that the QSVT can
be efficiently "dequantized" for low-rank matrices, and discussed its
implication to quantum machine learning. In this work, motivated by
establishing the superiority of quantum algorithms for quantum chemistry and
making progress on the quantum PCP conjecture, we focus on the other main class
of matrices considered in applications of the QSVT, sparse matrices.
We first show how to efficiently "dequantize", with arbitrarily small
constant precision, the QSVT associated with a low-degree polynomial. We apply
this technique to design classical algorithms that estimate, with constant
precision, the singular values of a sparse matrix. We show in particular that a
central computational problem considered by quantum algorithms for quantum
chemistry (estimating the ground state energy of a local Hamiltonian when
given, as an additional input, a state sufficiently close to the ground state)
can be solved efficiently with constant precision on a classical computer. As a
complementary result, we prove that with inverse-polynomial precision, the same
problem becomes BQP-complete. This gives theoretical evidence for the
superiority of quantum algorithms for chemistry, and strongly suggests that
said superiority stems from the improved precision achievable in the quantum
setting. We also discuss how this dequantization technique may help make
progress on the central quantum PCP conjecture.}},
author = {{Gharibian, Sevag and Gall, François Le}},
booktitle = {{Proceedings of the 54th ACM Symposium on Theory of Computing (STOC)}},
pages = {{19--32}},
title = {{{Dequantizing the Quantum Singular Value Transformation: Hardness and Applications to Quantum Chemistry and the Quantum PCP Conjecture}}},
year = {{2022}},
}
@article{31057,
abstract = {{In this paper we give an overview over some aspects of the modern mathematical theory of Ruelle resonances for chaotic, i.e. uniformly hyperbolic, dynamical systems and their implications in physics. First we recall recent developments in the mathematical theory of resonances, in particular how invariant Ruelle distributions arise as residues of weighted zeta functions. Then we derive a correspondence between weighted and semiclassical zeta functions in the setting of negatively curved surfaces. Combining this with results of Hilgert, Guillarmou and Weich yields a high frequency interpretation of invariant Ruelle distributions as quantum mechanical matrix coefficients in constant negative curvature. We finish by presenting numerical calculations of phase space distributions in the more physical setting of 3-disk scattering systems.}},
author = {{Barkhofen, Sonja and Schütte, Philipp and Weich, Tobias}},
journal = {{Journal of Physics A: Mathematical and Theoretical}},
number = {{24}},
publisher = {{IOP Publishing Ltd}},
title = {{{Semiclassical formulae For Wigner distributions}}},
doi = {{10.1088/1751-8121/ac6d2b}},
volume = {{55}},
year = {{2022}},
}
@article{35322,
author = {{Bux, Kai-Uwe and Hilgert, Joachim and Weich, Tobias}},
issn = {{1664-039X}},
journal = {{Journal of Spectral Theory}},
keywords = {{Geometry and Topology, Mathematical Physics, Statistical and Nonlinear Physics}},
number = {{2}},
pages = {{659--681}},
publisher = {{European Mathematical Society - EMS - Publishing House GmbH}},
title = {{{Poisson transforms for trees of bounded degree}}},
doi = {{10.4171/jst/414}},
volume = {{12}},
year = {{2022}},
}
@article{39025,
author = {{Meyer-Scott, Evan and Prasannan, Nidhin and Dhand, Ish and Eigner, Christof and Quiring, Viktor and Barkhofen, Sonja and Brecht, Benjamin and Plenio, Martin B. and Silberhorn, Christine}},
issn = {{0031-9007}},
journal = {{Physical Review Letters}},
keywords = {{General Physics and Astronomy}},
number = {{15}},
publisher = {{American Physical Society (APS)}},
title = {{{Scalable Generation of Multiphoton Entangled States by Active Feed-Forward and Multiplexing}}},
doi = {{10.1103/physrevlett.129.150501}},
volume = {{129}},
year = {{2022}},
}
@article{40273,
author = {{Meyer-Scott, Evan and Prasannan, Nidhin and Dhand, Ish and Eigner, Christof and Quiring, Viktor and Barkhofen, Sonja and Brecht, Benjamin and Plenio, Martin B. and Silberhorn, Christine}},
issn = {{0031-9007}},
journal = {{Physical Review Letters}},
keywords = {{General Physics and Astronomy}},
number = {{15}},
publisher = {{American Physical Society (APS)}},
title = {{{Scalable Generation of Multiphoton Entangled States by Active Feed-Forward and Multiplexing}}},
doi = {{10.1103/physrevlett.129.150501}},
volume = {{129}},
year = {{2022}},
}
@article{33450,
author = {{Hamilton, Craig S. and Christ, Regina and Barkhofen, Sonja and Barnett, Stephen M. and Jex, Igor and Silberhorn, Christine}},
issn = {{2469-9926}},
journal = {{Physical Review A}},
number = {{4}},
publisher = {{American Physical Society (APS)}},
title = {{{Quantum-state creation in nonlinear-waveguide arrays}}},
doi = {{10.1103/physreva.105.042622}},
volume = {{105}},
year = {{2022}},
}
@inproceedings{41879,
author = {{Sbresny, F and Hanschke, L and Schöll, E and Rauhaus, W and Scaparra, B and Boos, K and Casalengua, E.Zubizarreta and H. Riedl, H and Valle, E Del and Finley, J.J and Jöns, Klaus D. and Müller, K}},
title = {{{Stimulated Generation of Indistinguishable Single Photons from a Quantum Ladder System}}},
volume = {{128}},
year = {{2022}},
}
@inproceedings{41880,
author = {{Turunen, M and Brotons-Gisbert, M and Dai, Y and Wang, Y and Scerri, E and Bonato, C and Jöns, Klaus D. and Sun, Z and Gerardot, B.D}},
number = {{4}},
pages = {{219--236}},
title = {{{Quantum photonics with layered 2D materials}}},
volume = {{4}},
year = {{2022}},
}
@inproceedings{41881,
author = {{Pelucchi, E and Fagas, G and Aharonovich, I and Englund, D and Figueroa, E and Gong, Q and Hannes, H and Liu, J and Lu, C-Y and Matsuda, N and Pan, J.W and Schreck, F and Sciarrino, F and Silberhorn, Christine and Wang, J and Jöns, Klaus D.}},
number = {{3}},
pages = {{194--208}},
title = {{{The potential and global outlook of integrated photonics for quantum technologi}}},
volume = {{4}},
year = {{2022}},
}
@article{34700,
author = {{Gharibian, Sevag and Santha, Miklos and Sikora, Jamie and Sundaram, Aarthi and Yirka, Justin}},
issn = {{1016-3328}},
journal = {{Computational Complexity}},
keywords = {{Computational Mathematics, Computational Theory and Mathematics, General Mathematics, Theoretical Computer Science}},
number = {{2}},
publisher = {{Springer Science and Business Media LLC}},
title = {{{Quantum generalizations of the polynomial hierarchy with applications to QMA(2)}}},
doi = {{10.1007/s00037-022-00231-8}},
volume = {{31}},
year = {{2022}},
}
@article{28254,
abstract = {{With the rapid advances of functional dielectric metasurfaces and their integration on on-chip nanophotonic devices, the necessity of metasurfaces working in different environments, especially in biological applications, arose. However, the metasurfaces’ performance is tied to the unit cell’s efficiency and ultimately the surrounding environment it was designed for, thus reducing its applicability if exposed to altering refractive index media. Here, we report a method to increase a metasurface’s versatility by covering the high-index metasurface with a low index porous SiO2 film, protecting the metasurface from environmental changes while keeping the working efficiency unchanged. We show, that a covered metasurface retains its functionality even when exposed to fluidic environments.}},
author = {{Geromel, René and Weinberger, Christian and Brormann, Katja and Tiemann, Michael and Zentgraf, Thomas}},
issn = {{2159-3930}},
journal = {{Optical Materials Express}},
number = {{1}},
pages = {{13--21}},
publisher = {{Optica}},
title = {{{Porous SiO2 coated dielectric metasurface with consistent performance independent of environmental conditions}}},
doi = {{10.1364/ome.444264}},
volume = {{12}},
year = {{2022}},
}
@article{37318,
abstract = {{Abstract
The interaction between quantum light and matter is being intensively studied for systems that are enclosed in high-Q cavities which strongly enhance the light–matter coupling. Cavities with low Q-factors are generally given less attention due to their high losses that quickly destroy quantum systems. However, bad cavities can be utilized for several applications, where lower Q-factors are required, e.g., to increase the spectral width of the cavity mode. In this work, we demonstrate that low-Q cavities can be beneficial for preparing specific electronic steady states when certain quantum states of light are applied. We investigate the interaction between quantum light with various statistics and matter represented by a Λ-type three-level system in lossy cavities, assuming that cavity losses are the dominant loss mechanism. We show that cavity losses lead to non-trivial electronic steady states that can be controlled by the loss rate and the initial statistics of the quantum fields. We discuss the mechanism of the formation of such steady states on the basis of the equations of motion and present both analytical expressions and numerical simulations for such steady states.}},
author = {{Rose, Hendrik and Tikhonova, O V and Meier, Torsten and Sharapova, Polina}},
issn = {{1367-2630}},
journal = {{New Journal of Physics}},
keywords = {{General Physics and Astronomy}},
number = {{6}},
publisher = {{IOP Publishing}},
title = {{{Steady states of Λ-type three-level systems excited by quantum light with various photon statistics in lossy cavities}}},
doi = {{10.1088/1367-2630/ac74d8}},
volume = {{24}},
year = {{2022}},
}
@article{37319,
author = {{Grisard, S. and Rose, Hendrik and Trifonov, A. V. and Reichhardt, R. and Reiter, D. E. and Reichelt, Matthias and Schneider, C. and Kamp, M. and Höfling, S. and Bayer, M. and Meier, Torsten and Akimov, I. A.}},
issn = {{2469-9950}},
journal = {{Physical Review B}},
number = {{20}},
publisher = {{American Physical Society (APS)}},
title = {{{Multiple Rabi rotations of trions in InGaAs quantum dots observed by photon echo spectroscopy with spatially shaped laser pulses}}},
doi = {{10.1103/physrevb.106.205408}},
volume = {{106}},
year = {{2022}},
}
@inproceedings{37327,
author = {{Rose, Hendrik and Tikhonova, Olga V. and Meier, Torsten and Sharapova, Polina}},
booktitle = {{Ultrafast Phenomena and Nanophotonics XXVI}},
editor = {{Betz, Markus and Elezzabi, Abdulhakem Y.}},
title = {{{Theoretical analysis of correlations between two quantum fields exciting a three-level system using the cluster-expansion approach}}},
doi = {{10.1117/12.2608528}},
volume = {{11999}},
year = {{2022}},
}
@article{40523,
abstract = {{AbstractTailored nanoscale quantum light sources, matching the specific needs of use cases, are crucial building blocks for photonic quantum technologies. Several different approaches to realize solid-state quantum emitters with high performance have been pursued and different concepts for energy tuning have been established. However, the properties of the emitted photons are always defined by the individual quantum emitter and can therefore not be controlled with full flexibility. Here we introduce an all-optical nonlinear method to tailor and control the single photon emission. We demonstrate a laser-controlled down-conversion process from an excited state of a semiconductor quantum three-level system. Based on this concept, we realize energy tuning and polarization control of the single photon emission with a control-laser field. Our results mark an important step towards tailored single photon emission from a photonic quantum system based on quantum optical principles.}},
author = {{Jonas, B. and Heinze, Dirk Florian and Schöll, E. and Kallert, P. and Langer, T. and Krehs, S. and Widhalm, A. and Jöns, Klaus and Reuter, Dirk and Schumacher, Stefan and Zrenner, Artur}},
issn = {{2041-1723}},
journal = {{Nature Communications}},
keywords = {{General Physics and Astronomy, General Biochemistry, Genetics and Molecular Biology, General Chemistry, Multidisciplinary}},
number = {{1}},
publisher = {{Springer Science and Business Media LLC}},
title = {{{Nonlinear down-conversion in a single quantum dot}}},
doi = {{10.1038/s41467-022-28993-3}},
volume = {{13}},
year = {{2022}},
}
@article{40431,
author = {{Praschan, Tom and Heinze, Dirk and Breddermann, Dominik and Zrenner, Artur and Walther, Andrea and Schumacher, Stefan}},
issn = {{2469-9950}},
journal = {{Physical Review B}},
number = {{4}},
publisher = {{American Physical Society (APS)}},
title = {{{Pulse shaping for on-demand emission of single Raman photons from a quantum-dot biexciton}}},
doi = {{10.1103/physrevb.105.045302}},
volume = {{105}},
year = {{2022}},
}
@article{33484,
abstract = {{We study the DC conductivity in potassium titanyl phosphate (KTiOPO4, KTP) and its isomorphs KTiOAsO4 (KTA) and Rb1%K99%TiOPO4 (RKTP) and introduce a method by which to reduce the overall ionic conductivity in KTP by a potassium nitrate treatment. Furthermore, we create so-called gray tracking in KTP and investigate the ionic conductivity in theses areas. A local unintended reduction of the ionic conductivity is observed in the gray-tracked regions, which also induce additional optical absorption in the material. We show that a thermal treatment in an oxygen-rich atmosphere removes the gray tracking and brings the ionic conductivity as well as the optical transmission back to the original level. These studies can help to choose the best material and treatment for specific applications.}},
author = {{Padberg, Laura and Quiring, Viktor and Bocchini, Adriana and Santandrea, Matteo and Gerstmann, Uwe and Schmidt, Wolf Gero and Silberhorn, Christine and Eigner, Christof}},
issn = {{2073-4352}},
journal = {{Crystals}},
pages = {{1359}},
title = {{{DC Ionic Conductivity in KTP and Its Isomorphs: Properties, Methods for Suppression, and Its Connection to Gray Tracking}}},
doi = {{10.3390/cryst12101359}},
volume = {{12}},
year = {{2022}},
}
@article{34884,
author = {{Prasannan, Nidhin and Sperling, Jan and Brecht, Benjamin and Silberhorn, Christine}},
issn = {{0031-9007}},
journal = {{Physical Review Letters}},
keywords = {{General Physics and Astronomy}},
number = {{26}},
publisher = {{American Physical Society (APS)}},
title = {{{Direct Measurement of Higher-Order Nonlinear Polarization Squeezing}}},
doi = {{10.1103/physrevlett.129.263601}},
volume = {{129}},
year = {{2022}},
}
@article{32068,
abstract = {{Inspired by plant grafting, grafted vortex beams can be formed through grafting two or more helical phase profiles of optical vortex beams. Recently, grafted perfect vortex beams (GPVBs) have attracted much attention due to their unique optical properties and potential applications. However, the current method to generate and manipulate GPVBs requires a complex and bulky optical system, hindering further investigation and limiting its practical applications. Here, a compact metasurface approach for generating and manipulating GPVBs in multiple channels is proposed and demonstrated, which eliminates the need for such a complex optical setup. A single metasurface is utilized to realize various superpositions of GPVBs with different combinations of topological charges in four channels, leading to asymmetric singularity distributions. The positions of singularities in the superimposed beam can be further modulated by introducing an initial phase difference in the metasurface design. The work demonstrates a compact metasurface platform that performs a sophisticated optical task that is very challenging with conventional optics, opening opportunities for the investigation and applications of GPVBs in a wide range of emerging application areas, such as singular optics and quantum science.}},
author = {{Ahmed, Hammad and Intaravanne, Yuttana and Ming, Yang and Ansari, Muhammad Afnan and Buller, Gerald S. and Zentgraf, Thomas and Chen, Xianzhong}},
issn = {{0935-9648}},
journal = {{Advanced Materials}},
keywords = {{Mechanical Engineering, Mechanics of Materials, General Materials Science}},
number = {{30}},
publisher = {{Wiley}},
title = {{{Multichannel Superposition of Grafted Perfect Vortex Beams}}},
doi = {{10.1002/adma.202203044}},
volume = {{34}},
year = {{2022}},
}
@inproceedings{34238,
abstract = {{A monolithically integrated electronic-photonic Mach-Zehnder modulator is presented, incorporating electronic linear drivers along photonic components. An electro-optical 3 dB & 6 dB bandwidth of 24 GHz and 34 GHz respectively was measured. The on-chip drivers decrease the V
π
by a factor of 10.}},
author = {{Kress, Christian and Schwabe, Tobias and Rhee, Hanjo and Kerman, Sarp and Scheytt, J. Christoph}},
booktitle = {{Optica Advanced Photonics Congress 2022}},
publisher = {{Optica Publishing Group}},
title = {{{Broadband Mach-Zehnder Modulator with Linear Driver in Electronic-Photonic Co-Integrated Platform}}},
doi = {{10.1364/iprsn.2022.im4c.1}},
year = {{2022}},
}