TY - JOUR

T1 - Quantum imaging beyond the standard-quantum limit and phase distillation

AU - Schaffrath, Simon

AU - Derr, Daniel

AU - Gräfe, Markus

AU - Giese, Enno

N1 - Funding Information: We thank Jorge Fuenzalida, Sebastian Töpfer, and Sergio Adrián Tovar Pérez for fruitful discussions. The INTENTAS Project is supported by the German Space Agency at the German Aerospace Center (Deutsche Raumfahrtagentur im Deutschen Zentrum für Luft- und Raumfahrt, DLR) with funds provided by the German Federal Ministry for Economic Affairs and Climate Action (Bundesministerium für Wirtschaft und Klimaschutz) due to an enactment of the German Bundestag under Grant No. 50WM2177 (INTENTAS). E G thanks the German Research Foundation (Deutsche Forschungsgemeinschaft) for a Mercator Fellowship within CRC 1227 (DQ-mat). We acknowledge funding from the German Federal Ministry of Education and Research (Bundesministerium für Bildung und Forschung) within the program ‘quantum technologies—from basic research to market’ under Grant No. 13N16496 (QUANCER).

PY - 2024/2/9

Y1 - 2024/2/9

N2 - Quantum sensing using non-linear interferometers (NLIs) offers the possibility of bicolour imaging, using light that never interacted with the object of interest, and provides a way to achieve phase supersensitivity, i.e. a Heisenberg-type scaling of the phase uncertainty. Such a scaling behaviour is extremely susceptible to noise and only arises at specific phases that define the optimal working point (WP) of the device. While phase-shifting algorithms are to some degree robust against the deleterious effects induced by noise they extract an image by tuning the interferometer phase over a broad range, implying an operation beyond the WP. In our theoretical study, we investigate both the spontaneous and the high-gain regime of operation of an NLI. In fact, in the spontaneous regime using a distillation technique and operating at the WP leads to a qualitatively similar behaviour. In the high-gain regime, however, typical distillation techniques inherently forbid a scaling better than the standard-quantum limit, as a consequence of the photon statistics of squeezed vacuum. In contrast, an operation at the WP still may lead to a sensitivity below shot noise, even in the presence of noise. Therefore, this procedure opens the perspective of bicolour imaging with a better than shot-noise phase uncertainty by working in the vicinity of the WP. Our results transfer quantum imaging distillation in a noisy environment to the high-gain regime with the ultimate goal of harnessing its full potential by combining bicolour imaging and phase supersensitivity.

AB - Quantum sensing using non-linear interferometers (NLIs) offers the possibility of bicolour imaging, using light that never interacted with the object of interest, and provides a way to achieve phase supersensitivity, i.e. a Heisenberg-type scaling of the phase uncertainty. Such a scaling behaviour is extremely susceptible to noise and only arises at specific phases that define the optimal working point (WP) of the device. While phase-shifting algorithms are to some degree robust against the deleterious effects induced by noise they extract an image by tuning the interferometer phase over a broad range, implying an operation beyond the WP. In our theoretical study, we investigate both the spontaneous and the high-gain regime of operation of an NLI. In fact, in the spontaneous regime using a distillation technique and operating at the WP leads to a qualitatively similar behaviour. In the high-gain regime, however, typical distillation techniques inherently forbid a scaling better than the standard-quantum limit, as a consequence of the photon statistics of squeezed vacuum. In contrast, an operation at the WP still may lead to a sensitivity below shot noise, even in the presence of noise. Therefore, this procedure opens the perspective of bicolour imaging with a better than shot-noise phase uncertainty by working in the vicinity of the WP. Our results transfer quantum imaging distillation in a noisy environment to the high-gain regime with the ultimate goal of harnessing its full potential by combining bicolour imaging and phase supersensitivity.

KW - non-linear interferometer

KW - phase-shifting algorithm

KW - quantum imaging

KW - quantum metrology

KW - squeezing

KW - standard quantum limit

KW - supersensitivity

UR - http://www.scopus.com/inward/record.url?scp=85185194998&partnerID=8YFLogxK

U2 - 10.48550/arXiv.2311.12782

DO - 10.48550/arXiv.2311.12782

M3 - Article

AN - SCOPUS:85185194998

VL - 26

JO - New journal of physics

JF - New journal of physics

SN - 1367-2630

M1 - 023018

ER -