---
_id: '63744'
abstract:
- lang: eng
text: Orbital angular momentum (OAM) modes are an important resource used in various
branches of quantum science and technology due to their unique helical structure
and countably infinite basis. Generating light that simultaneously carries high-order
orbital angular momenta and exhibits quantum correlations is a challenging task.
In this work, we present a theoretical approach to the generation of correlated
Schmidt modes carrying OAM via parametric down-conversion (PDC) in cascaded nonlinear
systems (nonlinear interferometers) pumped by Laguerre–Gaussian beams. We demonstrate
how the number of generated modes and their population can be controlled by varying
the pump parameters, the gain of the PDC process, and the distance between the
crystals. We investigate the angular displacement measurement uncertainty of these
interferometers and demonstrate that it can overcome the classical shot noise
limit.
article_number: '016112'
article_type: original
author:
- first_name: Dennis
full_name: Scharwald, Dennis
id: '55907'
last_name: Scharwald
orcid: 0009-0007-5654-5412
- first_name: Lucas
full_name: Gehse, Lucas
last_name: Gehse
- first_name: Polina
full_name: Sharapova, Polina
id: '60286'
last_name: Sharapova
citation:
ama: Scharwald D, Gehse L, Sharapova P. Schmidt modes carrying orbital angular momentum
generated by cascaded systems pumped with Laguerre–Gaussian beams. APL Photonics.
2025;10(1). doi:10.1063/5.0229802
apa: Scharwald, D., Gehse, L., & Sharapova, P. (2025). Schmidt modes carrying
orbital angular momentum generated by cascaded systems pumped with Laguerre–Gaussian
beams. APL Photonics, 10(1), Article 016112. https://doi.org/10.1063/5.0229802
bibtex: '@article{Scharwald_Gehse_Sharapova_2025, title={Schmidt modes carrying
orbital angular momentum generated by cascaded systems pumped with Laguerre–Gaussian
beams}, volume={10}, DOI={10.1063/5.0229802},
number={1016112}, journal={APL Photonics}, publisher={AIP Publishing}, author={Scharwald,
Dennis and Gehse, Lucas and Sharapova, Polina}, year={2025} }'
chicago: Scharwald, Dennis, Lucas Gehse, and Polina Sharapova. “Schmidt Modes Carrying
Orbital Angular Momentum Generated by Cascaded Systems Pumped with Laguerre–Gaussian
Beams.” APL Photonics 10, no. 1 (2025). https://doi.org/10.1063/5.0229802.
ieee: 'D. Scharwald, L. Gehse, and P. Sharapova, “Schmidt modes carrying orbital
angular momentum generated by cascaded systems pumped with Laguerre–Gaussian beams,”
APL Photonics, vol. 10, no. 1, Art. no. 016112, 2025, doi: 10.1063/5.0229802.'
mla: Scharwald, Dennis, et al. “Schmidt Modes Carrying Orbital Angular Momentum
Generated by Cascaded Systems Pumped with Laguerre–Gaussian Beams.” APL Photonics,
vol. 10, no. 1, 016112, AIP Publishing, 2025, doi:10.1063/5.0229802.
short: D. Scharwald, L. Gehse, P. Sharapova, APL Photonics 10 (2025).
date_created: 2026-01-26T15:48:54Z
date_updated: 2026-02-01T13:19:20Z
department:
- _id: '15'
- _id: '569'
- _id: '170'
- _id: '35'
- _id: '429'
doi: 10.1063/5.0229802
intvolume: ' 10'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://pubs.aip.org/aip/app/article-pdf/doi/10.1063/5.0229802/20352749/016112_1_5.0229802.pdf
oa: '1'
project:
- _id: '53'
name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten
zu funktionellen Strukturen'
- _id: '56'
name: TRR 142 - Project Area C
- _id: '174'
name: 'TRR 142 ; TP: C10: Erzeugung und Charakterisierung von Quantenlicht in nichtlinearen
Systemen: Eine theoretische Analyse'
- _id: '52'
name: Computing Resources Provided by the Paderborn Center for Parallel Computing
publication: APL Photonics
publication_identifier:
issn:
- 2378-0967
publication_status: published
publisher: AIP Publishing
status: public
title: Schmidt modes carrying orbital angular momentum generated by cascaded systems
pumped with Laguerre–Gaussian beams
type: journal_article
user_id: '55907'
volume: 10
year: '2025'
...
---
_id: '63745'
abstract:
- lang: eng
text: Multimode squeezed light is an increasingly popular tool in photonic quantum
technologies, including sensing, imaging, and computation. Meanwhile, the existing
methods of its characterization are technically complicated, which reduces the
level of squeezing, and mostly deal with a single mode at a time. Here, for the
first time, to the best of our knowledge, we employ optical parametric amplification
to characterize multiple squeezing eigenmodes simultaneously. We retrieve the
shapes and squeezing degrees of all modes at once through direct detection followed
by modal decomposition. This method is tolerant to inefficient detection and does
not require a local oscillator. For a spectrally and spatially multimode squeezed
vacuum, we characterize eight strongest spatial modes, obtaining squeezing and
anti-squeezing values of up to −5.2 ± 0.2 dB and 8.6 ± 0.3 dB, respectively, despite
the 50% detection loss. This work, being the first exploration of an optical parametric
amplifier’s multimode capability for squeezing detection, paves the way for the
real-time detection of multimode squeezing.
article_number: '36'
article_type: original
author:
- first_name: Ismail
full_name: Barakat, Ismail
last_name: Barakat
- first_name: Mahmoud
full_name: Kalash, Mahmoud
last_name: Kalash
- first_name: Dennis
full_name: Scharwald, Dennis
id: '55907'
last_name: Scharwald
orcid: 0009-0007-5654-5412
- first_name: Polina
full_name: Sharapova, Polina
id: '60286'
last_name: Sharapova
- first_name: Norbert
full_name: Lindlein, Norbert
last_name: Lindlein
- first_name: Maria
full_name: Chekhova, Maria
last_name: Chekhova
citation:
ama: Barakat I, Kalash M, Scharwald D, Sharapova P, Lindlein N, Chekhova M. Simultaneous
measurement of multimode squeezing through multimode phase-sensitive amplification.
Optica Quantum. 2025;3(1). doi:10.1364/opticaq.524682
apa: Barakat, I., Kalash, M., Scharwald, D., Sharapova, P., Lindlein, N., &
Chekhova, M. (2025). Simultaneous measurement of multimode squeezing through multimode
phase-sensitive amplification. Optica Quantum, 3(1), Article 36.
https://doi.org/10.1364/opticaq.524682
bibtex: '@article{Barakat_Kalash_Scharwald_Sharapova_Lindlein_Chekhova_2025, title={Simultaneous
measurement of multimode squeezing through multimode phase-sensitive amplification},
volume={3}, DOI={10.1364/opticaq.524682},
number={136}, journal={Optica Quantum}, publisher={Optica Publishing Group}, author={Barakat,
Ismail and Kalash, Mahmoud and Scharwald, Dennis and Sharapova, Polina and Lindlein,
Norbert and Chekhova, Maria}, year={2025} }'
chicago: Barakat, Ismail, Mahmoud Kalash, Dennis Scharwald, Polina Sharapova, Norbert
Lindlein, and Maria Chekhova. “Simultaneous Measurement of Multimode Squeezing
through Multimode Phase-Sensitive Amplification.” Optica Quantum 3, no.
1 (2025). https://doi.org/10.1364/opticaq.524682.
ieee: 'I. Barakat, M. Kalash, D. Scharwald, P. Sharapova, N. Lindlein, and M. Chekhova,
“Simultaneous measurement of multimode squeezing through multimode phase-sensitive
amplification,” Optica Quantum, vol. 3, no. 1, Art. no. 36, 2025, doi:
10.1364/opticaq.524682.'
mla: Barakat, Ismail, et al. “Simultaneous Measurement of Multimode Squeezing through
Multimode Phase-Sensitive Amplification.” Optica Quantum, vol. 3, no. 1,
36, Optica Publishing Group, 2025, doi:10.1364/opticaq.524682.
short: I. Barakat, M. Kalash, D. Scharwald, P. Sharapova, N. Lindlein, M. Chekhova,
Optica Quantum 3 (2025).
date_created: 2026-01-26T15:57:13Z
date_updated: 2026-02-10T22:44:44Z
department:
- _id: '15'
- _id: '569'
- _id: '170'
- _id: '35'
- _id: '429'
doi: 10.1364/opticaq.524682
intvolume: ' 3'
issue: '1'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://opg.optica.org/opticaq/viewmedia.cfm?uri=opticaq-3-1-36&seq=0
oa: '1'
project:
- _id: '53'
name: 'TRR 142: Maßgeschneiderte nichtlineare Photonik: Von grundlegenden Konzepten
zu funktionellen Strukturen'
- _id: '56'
name: TRR 142 - Project Area C
- _id: '174'
name: 'TRR 142 ; TP: C10: Erzeugung und Charakterisierung von Quantenlicht in nichtlinearen
Systemen: Eine theoretische Analyse'
- _id: '52'
name: Computing Resources Provided by the Paderborn Center for Parallel Computing
publication: Optica Quantum
publication_identifier:
issn:
- 2837-6714
publication_status: published
publisher: Optica Publishing Group
status: public
title: Simultaneous measurement of multimode squeezing through multimode phase-sensitive
amplification
type: journal_article
user_id: '55907'
volume: 3
year: '2025'
...
---
_id: '55900'
article_number: '043158'
author:
- first_name: Dennis
full_name: Scharwald, Dennis
id: '55907'
last_name: Scharwald
orcid: 0009-0007-5654-5412
- first_name: Torsten
full_name: Meier, Torsten
id: '344'
last_name: Meier
orcid: 0000-0001-8864-2072
- first_name: Polina
full_name: Sharapova, Polina
last_name: Sharapova
citation:
ama: Scharwald D, Meier T, Sharapova P. Phase sensitivity of spatially broadband
high-gain SU(1,1) interferometers. Physical Review Research. 2023;5(4).
doi:10.1103/physrevresearch.5.043158
apa: Scharwald, D., Meier, T., & Sharapova, P. (2023). Phase sensitivity of
spatially broadband high-gain SU(1,1) interferometers. Physical Review Research,
5(4), Article 043158. https://doi.org/10.1103/physrevresearch.5.043158
bibtex: '@article{Scharwald_Meier_Sharapova_2023, title={Phase sensitivity of spatially
broadband high-gain SU(1,1) interferometers}, volume={5}, DOI={10.1103/physrevresearch.5.043158},
number={4043158}, journal={Physical Review Research}, publisher={American Physical
Society (APS)}, author={Scharwald, Dennis and Meier, Torsten and Sharapova, Polina},
year={2023} }'
chicago: Scharwald, Dennis, Torsten Meier, and Polina Sharapova. “Phase Sensitivity
of Spatially Broadband High-Gain SU(1,1) Interferometers.” Physical Review
Research 5, no. 4 (2023). https://doi.org/10.1103/physrevresearch.5.043158.
ieee: 'D. Scharwald, T. Meier, and P. Sharapova, “Phase sensitivity of spatially
broadband high-gain SU(1,1) interferometers,” Physical Review Research,
vol. 5, no. 4, Art. no. 043158, 2023, doi: 10.1103/physrevresearch.5.043158.'
mla: Scharwald, Dennis, et al. “Phase Sensitivity of Spatially Broadband High-Gain
SU(1,1) Interferometers.” Physical Review Research, vol. 5, no. 4, 043158,
American Physical Society (APS), 2023, doi:10.1103/physrevresearch.5.043158.
short: D. Scharwald, T. Meier, P. Sharapova, Physical Review Research 5 (2023).
date_created: 2024-08-30T04:48:05Z
date_updated: 2026-02-01T13:21:22Z
department:
- _id: '15'
- _id: '569'
- _id: '170'
- _id: '293'
- _id: '35'
- _id: '230'
- _id: '429'
- _id: '623'
- _id: '27'
doi: 10.1103/physrevresearch.5.043158
intvolume: ' 5'
issue: '4'
language:
- iso: eng
main_file_link:
- open_access: '1'
url: https://journals.aps.org/prresearch/pdf/10.1103/PhysRevResearch.5.043158
oa: '1'
project:
- _id: '53'
name: 'TRR 142: TRR 142 - Maßgeschneiderte nichtlineare Photonik: Von grundlegenden
Konzepten zu funktionellen Strukturen'
- _id: '56'
name: 'TRR 142 - C: TRR 142 - Project Area C'
- _id: '174'
name: 'TRR 142 - C10: TRR 142 - Erzeugung und Charakterisierung von Quantenlicht
in nichtlinearen Systemen: Eine theoretische Analyse (C10*)'
- _id: '52'
name: 'PC2: Computing Resources Provided by the Paderborn Center for Parallel Computing'
publication: Physical Review Research
publication_identifier:
issn:
- 2643-1564
publication_status: published
publisher: American Physical Society (APS)
status: public
title: Phase sensitivity of spatially broadband high-gain SU(1,1) interferometers
type: journal_article
user_id: '55907'
volume: 5
year: '2023'
...