---
_id: '43246'
abstract:
- lang: eng
text: The biexciton-exciton emission cascade commonly used in quantum-dot systems
to generate polarization entanglement yields photons with intrinsically limited
indistinguishability. In the present work we focus on the generation of pairs
of photons with high degrees of polarization entanglement and simultaneously high
indistinguishibility. We achieve this goal by selectively reducing the biexciton
lifetime with an optical resonator. We demonstrate that a suitably tailored circular
Bragg reflector fulfills the requirements of sufficient selective Purcell enhancement
of biexciton emission paired with spectrally broad photon extraction and two-fold
degenerate optical modes. Our in-depth theoretical study combines (i) the optimization
of realistic photonic structures solving Maxwell's equations from which model
parameters are extracted as input for (ii) microscopic simulations of quantum-dot
cavity excitation dynamics with full access to photon properties. We report non-trivial
dependencies on system parameters and use the predictive power of our combined
theoretical approach to determine the optimal range of Purcell enhancement that
maximizes indistinguishability and entanglement to near unity values in the telecom
C-band at $1550\,\mathrm{nm}$.
author:
- first_name: David
full_name: Bauch, David
last_name: Bauch
- first_name: Dustin
full_name: Siebert, Dustin
last_name: Siebert
- first_name: Klaus
full_name: Jöns, Klaus
id: '85353'
last_name: Jöns
- first_name: Jens
full_name: Förstner, Jens
id: '158'
last_name: Förstner
orcid: 0000-0001-7059-9862
- first_name: Stefan
full_name: Schumacher, Stefan
id: '27271'
last_name: Schumacher
orcid: 0000-0003-4042-4951
citation:
ama: Bauch D, Siebert D, Jöns K, Förstner J, Schumacher S. On-demand indistinguishable
and entangled photons at telecom frequencies using tailored cavity designs. Published
online 2023.
apa: Bauch, D., Siebert, D., Jöns, K., Förstner, J., & Schumacher, S. (2023).
On-demand indistinguishable and entangled photons at telecom frequencies using
tailored cavity designs.
bibtex: '@article{Bauch_Siebert_Jöns_Förstner_Schumacher_2023, title={On-demand
indistinguishable and entangled photons at telecom frequencies using tailored
cavity designs}, author={Bauch, David and Siebert, Dustin and Jöns, Klaus and
Förstner, Jens and Schumacher, Stefan}, year={2023} }'
chicago: Bauch, David, Dustin Siebert, Klaus Jöns, Jens Förstner, and Stefan Schumacher.
“On-Demand Indistinguishable and Entangled Photons at Telecom Frequencies Using
Tailored Cavity Designs,” 2023.
ieee: D. Bauch, D. Siebert, K. Jöns, J. Förstner, and S. Schumacher, “On-demand
indistinguishable and entangled photons at telecom frequencies using tailored
cavity designs.” 2023.
mla: Bauch, David, et al. On-Demand Indistinguishable and Entangled Photons at
Telecom Frequencies Using Tailored Cavity Designs. 2023.
short: D. Bauch, D. Siebert, K. Jöns, J. Förstner, S. Schumacher, (2023).
date_created: 2023-03-31T13:22:05Z
date_updated: 2023-12-21T10:41:17Z
department:
- _id: '61'
- _id: '230'
- _id: '429'
- _id: '623'
- _id: '15'
- _id: '35'
- _id: '170'
- _id: '297'
keyword:
- tet_topic_phc
- tet_topic_qd
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://arxiv.org/pdf/2303.13871.pdf
oa: '1'
project:
- _id: '52'
name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing'
- _id: '173'
grant_number: '231447078'
name: 'TRR 142 - C09: TRR 142 - Subproject C09'
- _id: '167'
grant_number: '231447078'
name: 'TRR 142 - B06: TRR 142 - Subproject B06'
- _id: '53'
grant_number: '231447078'
name: 'TRR 142: TRR 142'
- _id: '55'
name: 'TRR 142 - B: TRR 142 - Project Area B'
- _id: '56'
name: 'TRR 142 - C: TRR 142 - Project Area C'
related_material:
record:
- id: '48599'
relation: later_version
status: public
status: public
title: On-demand indistinguishable and entangled photons at telecom frequencies using
tailored cavity designs
type: preprint
user_id: '16199'
year: '2023'
...
---
_id: '28413'
abstract:
- lang: eng
text: Optical traveling wave antennas offer unique opportunities to control and
selectively guide light into a specific direction, which renders them excellent
candidates for optical communication and sensing. These applications require state-of-the-art
engineering to reach optimized functionalities such as high directivity and radiation
efficiency, low sidelobe levels, broadband and tunable capabilities, and compact
design. In this work, we report on the numerical optimization of the directivity
of optical traveling wave antennas made from low-loss dielectric materials using
full-wave numerical simulations in conjunction with the particle swarm optimization
algorithm. The antennas are composed of a reflector and a director deposited on
a glass substrate, and an emitter placed in the feed gap between them serves as
an internal source of excitation. In particular, we analyze antennas with rectangular-
and horn-shaped directors made of either hafnium dioxide or silicon. The optimized
antennas produce highly directional emissions due to the presence of two dominant
guided TE modes in the director in addition to leaky modes. These guided modes
dominate the far-field emission pattern and govern the direction of the main lobe
emission, which predominately originates from the end facet of the director. Our
work also provides a comprehensive analysis of the modes, radiation patterns,
parametric influences, and bandwidths of the antennas, which highlights their
robust nature.
author:
- first_name: Henna
full_name: Farheen, Henna
last_name: Farheen
- first_name: Till
full_name: Leuteritz, Till
last_name: Leuteritz
- first_name: Stefan
full_name: Linden, Stefan
last_name: Linden
- first_name: Viktor
full_name: Myroshnychenko, Viktor
id: '46371'
last_name: Myroshnychenko
- first_name: Jens
full_name: Förstner, Jens
id: '158'
last_name: Förstner
orcid: 0000-0001-7059-9862
citation:
ama: Farheen H, Leuteritz T, Linden S, Myroshnychenko V, Förstner J. Optimization
of optical waveguide antennas for directive emission of light. Journal of the
Optical Society of America B. 2022;39(1):83. doi:10.1364/josab.438514
apa: Farheen, H., Leuteritz, T., Linden, S., Myroshnychenko, V., & Förstner,
J. (2022). Optimization of optical waveguide antennas for directive emission of
light. Journal of the Optical Society of America B, 39(1), 83. https://doi.org/10.1364/josab.438514
bibtex: '@article{Farheen_Leuteritz_Linden_Myroshnychenko_Förstner_2022, title={Optimization
of optical waveguide antennas for directive emission of light}, volume={39}, DOI={10.1364/josab.438514}, number={1},
journal={Journal of the Optical Society of America B}, author={Farheen, Henna
and Leuteritz, Till and Linden, Stefan and Myroshnychenko, Viktor and Förstner,
Jens}, year={2022}, pages={83} }'
chicago: 'Farheen, Henna, Till Leuteritz, Stefan Linden, Viktor Myroshnychenko,
and Jens Förstner. “Optimization of Optical Waveguide Antennas for Directive Emission
of Light.” Journal of the Optical Society of America B 39, no. 1 (2022):
83. https://doi.org/10.1364/josab.438514.'
ieee: 'H. Farheen, T. Leuteritz, S. Linden, V. Myroshnychenko, and J. Förstner,
“Optimization of optical waveguide antennas for directive emission of light,”
Journal of the Optical Society of America B, vol. 39, no. 1, p. 83, 2022,
doi: 10.1364/josab.438514.'
mla: Farheen, Henna, et al. “Optimization of Optical Waveguide Antennas for Directive
Emission of Light.” Journal of the Optical Society of America B, vol. 39,
no. 1, 2022, p. 83, doi:10.1364/josab.438514.
short: H. Farheen, T. Leuteritz, S. Linden, V. Myroshnychenko, J. Förstner, Journal
of the Optical Society of America B 39 (2022) 83.
date_created: 2021-12-08T07:14:39Z
date_updated: 2022-01-06T06:58:04Z
ddc:
- '530'
department:
- _id: '61'
- _id: '230'
- _id: '429'
doi: 10.1364/josab.438514
file:
- access_level: local
content_type: application/pdf
creator: fossie
date_created: 2021-12-08T08:26:57Z
date_updated: 2021-12-08T08:26:57Z
embargo: 2022-12-08
embargo_to: open_access
file_id: '28417'
file_name: 2021-12 Farheen - JOSA B - Optimization of optical nanoantennas.pdf
file_size: 14029741
relation: main_file
- access_level: open_access
content_type: application/pdf
creator: fossie
date_created: 2021-12-08T08:29:49Z
date_updated: 2021-12-08T08:29:49Z
file_id: '28418'
file_name: 2021-12 Farheen - JOSA B - Optimization of optical nanoantennas SUPPLEMENTARY
MATERIAL.pdf
file_size: 655495
relation: supplementary_material
file_date_updated: 2021-12-08T08:29:49Z
has_accepted_license: '1'
intvolume: ' 39'
issue: '1'
keyword:
- tet_topic_opticalantenna
language:
- iso: eng
oa: '1'
page: '83'
project:
- _id: '53'
name: TRR 142
- _id: '56'
name: TRR 142 - Project Area C
- _id: '75'
name: TRR 142 - Subproject C5
- _id: '52'
name: Computing Resources Provided by the Paderborn Center for Parallel Computing
publication: Journal of the Optical Society of America B
publication_identifier:
issn:
- 0740-3224
- 1520-8540
publication_status: published
status: public
title: Optimization of optical waveguide antennas for directive emission of light
type: journal_article
user_id: '158'
volume: 39
year: '2022'
...
---
_id: '29075'
abstract:
- lang: eng
text: We study a double-scattering coherent mechanism of negative polarization (NP)
near opposition that is observed for powder-like surfaces. The problem is solved
numerically for absorbing structures with irregular constituents, cubes, spheres,
and ellipsoids larger than the wavelength of incident light. Our simulations show
that double scattering between two random irregular particles shows weak NP. Adding
one more particle significantly increases the relative contribution of double
scattering which enhances NP. Simulations with regular shapes and controlled geometric
parameters show that the interference mechanism is sensitive to the geometry of
the scattering system and can also result in no polarization or even strong enhancement
of positive polarization at backscattering.
author:
- first_name: Samer
full_name: Alhaddad, Samer
id: '42456'
last_name: Alhaddad
- first_name: Yevgen
full_name: Grynko, Yevgen
id: '26059'
last_name: Grynko
- first_name: Henna
full_name: Farheen, Henna
last_name: Farheen
- first_name: Jens
full_name: Förstner, Jens
id: '158'
last_name: Förstner
orcid: 0000-0001-7059-9862
citation:
ama: Alhaddad S, Grynko Y, Farheen H, Förstner J. Numerical analysis of the coherent
mechanism producing negative polarization at backscattering from systems of absorbing
particles. Optics Letters. 2022;47(1):58. doi:10.1364/ol.444953
apa: Alhaddad, S., Grynko, Y., Farheen, H., & Förstner, J. (2022). Numerical
analysis of the coherent mechanism producing negative polarization at backscattering
from systems of absorbing particles. Optics Letters, 47(1), 58.
https://doi.org/10.1364/ol.444953
bibtex: '@article{Alhaddad_Grynko_Farheen_Förstner_2022, title={Numerical analysis
of the coherent mechanism producing negative polarization at backscattering from
systems of absorbing particles}, volume={47}, DOI={10.1364/ol.444953},
number={1}, journal={Optics Letters}, author={Alhaddad, Samer and Grynko, Yevgen
and Farheen, Henna and Förstner, Jens}, year={2022}, pages={58} }'
chicago: 'Alhaddad, Samer, Yevgen Grynko, Henna Farheen, and Jens Förstner. “Numerical
Analysis of the Coherent Mechanism Producing Negative Polarization at Backscattering
from Systems of Absorbing Particles.” Optics Letters 47, no. 1 (2022):
58. https://doi.org/10.1364/ol.444953.'
ieee: 'S. Alhaddad, Y. Grynko, H. Farheen, and J. Förstner, “Numerical analysis
of the coherent mechanism producing negative polarization at backscattering from
systems of absorbing particles,” Optics Letters, vol. 47, no. 1, p. 58,
2022, doi: 10.1364/ol.444953.'
mla: Alhaddad, Samer, et al. “Numerical Analysis of the Coherent Mechanism Producing
Negative Polarization at Backscattering from Systems of Absorbing Particles.”
Optics Letters, vol. 47, no. 1, 2022, p. 58, doi:10.1364/ol.444953.
short: S. Alhaddad, Y. Grynko, H. Farheen, J. Förstner, Optics Letters 47 (2022)
58.
date_created: 2021-12-21T13:49:29Z
date_updated: 2022-01-06T06:58:46Z
ddc:
- '530'
department:
- _id: '61'
- _id: '230'
- _id: '429'
doi: 10.1364/ol.444953
file:
- access_level: local
content_type: application/pdf
creator: fossie
date_created: 2021-12-21T13:53:47Z
date_updated: 2021-12-21T13:53:47Z
embargo: 2022-12-21
embargo_to: open_access
file_id: '29076'
file_name: 2022-01 Alhaddad - Optics Letter - Double Scattering.pdf
file_size: 3197213
relation: main_file
file_date_updated: 2021-12-21T13:53:47Z
has_accepted_license: '1'
intvolume: ' 47'
issue: '1'
keyword:
- tet_topic_scattering
language:
- iso: eng
page: '58'
project:
- _id: '52'
name: Computing Resources Provided by the Paderborn Center for Parallel Computing
publication: Optics Letters
publication_identifier:
issn:
- 0146-9592
- 1539-4794
publication_status: published
status: public
title: Numerical analysis of the coherent mechanism producing negative polarization
at backscattering from systems of absorbing particles
type: journal_article
user_id: '158'
volume: 47
year: '2022'
...
---
_id: '30387'
abstract:
- lang: eng
text: Resonant evanescent coupling can be utilized to selectively excite orbital
angular momentum (OAM) modes of high angular order supported by a thin circular
dielectric rod. Our 2.5-D hybrid-analytical coupled mode model combines the vectorial
fields associated with the fundamental TE- and TM-modes of a standard silicon
photonics slab waveguide, propagating at oblique angles with respect to the rod
axis, and the hybrid modes supported by the rod. One observes an efficient resonant
interaction in cases where the common axial wavenumber of the waves in the slab
matches the propagation constant of one or more modes of the rod. For certain
modes of high angular order, the incident wave is able to transfer its directionality
to the field in the fiber, exciting effectively only one of a pair of degenerate
OAM modes
author:
- first_name: Manfred
full_name: Hammer, Manfred
id: '48077'
last_name: Hammer
orcid: 0000-0002-6331-9348
- first_name: Lena
full_name: Ebers, Lena
id: '40428'
last_name: Ebers
- first_name: Jens
full_name: Förstner, Jens
id: '158'
last_name: Förstner
orcid: 0000-0001-7059-9862
citation:
ama: 'Hammer M, Ebers L, Förstner J. Resonant evanescent excitation of OAM modes
in a high-contrast circular step-index fiber. In: Andrews DL, Galvez EJ, Rubinsztein-Dunlop
H, eds. Complex Light and Optical Forces XVI. SPIE; 2022:120170F. doi:10.1117/12.2612179'
apa: Hammer, M., Ebers, L., & Förstner, J. (2022). Resonant evanescent excitation
of OAM modes in a high-contrast circular step-index fiber. In D. L. Andrews, E.
J. Galvez, & H. Rubinsztein-Dunlop (Eds.), Complex Light and Optical Forces
XVI (p. 120170F). SPIE. https://doi.org/10.1117/12.2612179
bibtex: '@inproceedings{Hammer_Ebers_Förstner_2022, title={Resonant evanescent excitation
of OAM modes in a high-contrast circular step-index fiber}, DOI={10.1117/12.2612179},
booktitle={Complex Light and Optical Forces XVI}, publisher={SPIE}, author={Hammer,
Manfred and Ebers, Lena and Förstner, Jens}, editor={Andrews, David L. and Galvez,
Enrique J. and Rubinsztein-Dunlop, Halina}, year={2022}, pages={120170F} }'
chicago: Hammer, Manfred, Lena Ebers, and Jens Förstner. “Resonant Evanescent Excitation
of OAM Modes in a High-Contrast Circular Step-Index Fiber.” In Complex Light
and Optical Forces XVI, edited by David L. Andrews, Enrique J. Galvez, and
Halina Rubinsztein-Dunlop, 120170F. SPIE, 2022. https://doi.org/10.1117/12.2612179.
ieee: 'M. Hammer, L. Ebers, and J. Förstner, “Resonant evanescent excitation of
OAM modes in a high-contrast circular step-index fiber,” in Complex Light and
Optical Forces XVI, 2022, p. 120170F, doi: 10.1117/12.2612179.'
mla: Hammer, Manfred, et al. “Resonant Evanescent Excitation of OAM Modes in a High-Contrast
Circular Step-Index Fiber.” Complex Light and Optical Forces XVI, edited
by David L. Andrews et al., SPIE, 2022, p. 120170F, doi:10.1117/12.2612179.
short: 'M. Hammer, L. Ebers, J. Förstner, in: D.L. Andrews, E.J. Galvez, H. Rubinsztein-Dunlop
(Eds.), Complex Light and Optical Forces XVI, SPIE, 2022, p. 120170F.'
date_created: 2022-03-21T10:12:58Z
date_updated: 2022-03-22T18:04:20Z
ddc:
- '530'
department:
- _id: '61'
- _id: '230'
- _id: '429'
doi: 10.1117/12.2612179
editor:
- first_name: David L.
full_name: Andrews, David L.
last_name: Andrews
- first_name: Enrique J.
full_name: Galvez, Enrique J.
last_name: Galvez
- first_name: Halina
full_name: Rubinsztein-Dunlop, Halina
last_name: Rubinsztein-Dunlop
file:
- access_level: open_access
content_type: application/pdf
creator: fossie
date_created: 2022-03-22T18:03:50Z
date_updated: 2022-03-22T18:03:50Z
file_id: '30444'
file_name: 2022-03 Hammer - SPIE Photonics West 2022 - Resonant evanescent excitation
of OAM modes in a high-contrast circular (official version).pdf
file_size: 2015899
relation: main_file
file_date_updated: 2022-03-22T18:03:50Z
has_accepted_license: '1'
keyword:
- tet_topic_waveguide
language:
- iso: eng
oa: '1'
page: 120170F
project:
- _id: '56'
name: 'TRR 142 - C: TRR 142 - Project Area C'
- _id: '53'
name: 'TRR 142: TRR 142'
- _id: '75'
name: 'TRR 142 - C5: TRR 142 - Subproject C5'
publication: Complex Light and Optical Forces XVI
publication_status: published
publisher: SPIE
status: public
title: Resonant evanescent excitation of OAM modes in a high-contrast circular step-index
fiber
type: conference
user_id: '158'
year: '2022'
...
---
_id: '30722'
abstract:
- lang: eng
text: In dieser Arbeit wird die elektromagnetische Wellenausbreitung in integrierten
optischen Wellenleitern mit Hilfe von halb analytischen und numerischen Simulationsmethoden
untersucht. Im ersten Teil werden 2-D Si/SiO2-Wellenleiterkonfigurationen mit
hohem Brechungsindexkontrast betrachtet. Die Strukturen werden mit halb geführten
Wellen unter schrägen Ausbreitungswinkeln angeregt. Dadurch kann die Leistungsübertragung
zu bestimmten ausgehenden Moden unterdrückt werden, wodurch vollständig verlustfreie
Systeme entstehen. Zusätzlich dient die Anregung mit einem seitlich begrenzten,
einfallenden Wellenbündel aus halb geführten Wellen dazu, praktisch relevantere
3-D Konfigurationen zu realisieren. Darüber hinaus wird eine schrittweise Winkelspektrum-Methode
vorgestellt, die es ermöglicht, in Kombination mit voll vektoriellen 2-D Finite-Elemente-Lösungen
für Teilprobleme mit geringerer Komplexität, die Wellenausbreitung in planaren,
linsenförmigen Wellenleitern numerisch in drei Raumrichtungen zu berechnen. Im
zweiten Teil dieser Arbeit wird die Ausbreitung in Wellenleiterstrukturen aus
Lithiumniobat untersucht, welche für quantenoptische Effekte genutzt werden. Zur
Detektion einzelner Photonen werden supraleitende Nanodrähte auf eindiffundierten
Lithiumniobat Wellenleitern mit zusätzlicher Taperschicht aus Silizium betrachtet.
Um die Wellenausbreitung in diesen 3-D Wellenleitern zu beschreiben, wird eine
einseitig gerichtete Finite-Elemente „Modal Matching“ Methode eingeführt. Abschließend
werden Rippenwellenleiter aus Lithiumniobat analysiert, die auf Siliziumdioxid
Plattformen aufgebracht sind. Der Schwerpunkt liegt hier auf dem nichtlinearen
„Parametric Down-Conversion“ Prozess, der für die Erzeugung verschränkter Photonen
verwendet wird.
- lang: eng
text: In this work, the electromagnetic wave propagation in integrated optical waveguides
is studied by using semi-analytical and numerical simulation methods. In the first
part, 2-D high-index contrast Si/SiO2 dielectric slab waveguide configurations
are investigated. The structures are excited with semi-guided waves at oblique
angles of propagation. Due to this, power transfer to specific outgoing modes
can be suppressed, resulting in completely lossless configurations. The excitation
is further examined for incoming, laterally confined wave bundles of semi-guided
waves to realize practically more relevant 3-D configurations. Additionally, a
stepwise angular spectrum method in combination with full vectorial 2-D finite
element solutions for subproblems of lower complexity to numerically simulate
the wave propagation in full 3-D planar lens-like waveguides is presented. In
the second part, the wave propagation in lithium niobate waveguide structures
is examined, which are used for quantum optical effects. On the one hand, superconducting
nanowires on titanium in-diffused lithium niobate waveguides with an additional
tapered silicon layer are used for single photon detection. The wave propagation
in these 3-D multiscale tapers is studied by introducing a unidirectional finite
element modal matching method. On the other hand, lithium niobate rib waveguides
on silicon dioxide platforms are analyzed, focusing on the nonlinear parametric
down-conversion process used for the generation of entangled photons.
author:
- first_name: Lena
full_name: Ebers, Lena
id: '40428'
last_name: Ebers
citation:
ama: Ebers L. Semi-Guided Waves in Integrated Optical Waveguide Structures.;
2022. doi:10.17619/UNIPB/1-1288
apa: Ebers, L. (2022). Semi-guided waves in integrated optical waveguide structures.
https://doi.org/10.17619/UNIPB/1-1288
bibtex: '@book{Ebers_2022, title={Semi-guided waves in integrated optical waveguide
structures}, DOI={10.17619/UNIPB/1-1288},
author={Ebers, Lena}, year={2022} }'
chicago: Ebers, Lena. Semi-Guided Waves in Integrated Optical Waveguide Structures,
2022. https://doi.org/10.17619/UNIPB/1-1288.
ieee: L. Ebers, Semi-guided waves in integrated optical waveguide structures.
2022.
mla: Ebers, Lena. Semi-Guided Waves in Integrated Optical Waveguide Structures.
2022, doi:10.17619/UNIPB/1-1288.
short: L. Ebers, Semi-Guided Waves in Integrated Optical Waveguide Structures, 2022.
date_created: 2022-03-29T18:42:08Z
date_updated: 2022-03-29T18:44:30Z
department:
- _id: '61'
- _id: '230'
doi: 10.17619/UNIPB/1-1288
keyword:
- tet_topic_waveguide
language:
- iso: eng
status: public
supervisor:
- first_name: Jens
full_name: Förstner, Jens
id: '158'
last_name: Förstner
orcid: 0000-0001-7059-9862
title: Semi-guided waves in integrated optical waveguide structures
type: dissertation
user_id: '158'
year: '2022'
...