Chinese Physics B

Enhanced phase sensitive amplification towards improving noise immunity

Hui Guo, Li Zhi, Hengxin Sun, Kui Liu, Jiangrui Gao

Published Feb 22, 2023• 0 citations

Abstract

Quantum states are essential resource for quantum-enhanced applications. Loss incurred in the distribution channel, however, dissipates the high signal-to-noise ratio advantage enjoyed by the squeezed state. Here, we first demonstrate noise immunity enhancement by using phase-sensitive amplifier (PSA) with measurement-based noiseless linear amplifier (MB-NLA). We explore the signal transfer capability with the amplifier in a noisy channel. The MB-NLA enhanced PSA has obvious suppression effect on channel noises, especially it has improvement for the noise contaminated signal. Better performance can be achieved by flexibly adjusting amplifier parameters. With the amplifier, it is promising to overcome the entanglement-distribution loss and show its superiority in squeezing based quantum sensing.

DOI: 10.1088/1674-1056/acbdeb

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