Loss-tolerant and quantum-enhanced interferometer by reversed squeezing processes

• Published in: Optics letters Vol. 48; no. 15; p. 3909
• Main Authors: Tian, Long, Yao, Wenxiu, Wu, Yimiao, Wang, Qingwei, Shen, Heng, Zheng, Yaohui, Peng, Kunchi
• Format: Journal Article
• Language: English
• Published: United States 01.08.2023
• ISSN: 1539-4794
• DOI: 10.1364/OL.487355

Reversed nonlinear dynamics is predicted to be capable of enhancing the quantum sensing in unprecedented ways. Here, we report the experimental demonstration of a loss-tolerant (external loss) and quantum-enhanced interferometer. Two cascaded optical parametric amplifiers are used to judiciously construct an interferometry with two orthogonal squeezing operation. As a consequence, a weak displacement introduced by a test cavity can be amplified for measurement, and the measured signal-to-noise ratio is better than that of both conventional photon shot-noise limited and squeezed-light assisted interferometers. We further confirm its superior loss-tolerant performance by varying the external losses and comparing with both conventional photon shot-noise limited and squeezed-light assisted configurations, illustrating the potential application in gravitational wave detection.