Experimental revival of squeezing-enhanced phase measurement in noisy quantum channels.

Abstract

Squeezing-enhanced optical phase estimation can significantly improve the measurement sensitivity and effectively enhance the signal-to-noise ratio. Investigating the influence of inevitable losses and noise in quantum channels on phase measurement is of paramount importance. Here, we analyze and experimentally demonstrate the evolution of squeezing enhancement in phase measurement, particularly under a non-Markovian decoherence model characterized by a correlated Gaussian noise in a bosonic environment. We show that in a noise-added channel, where the benefits of squeezing-enhanced phase measurement are seemingly lost, the performance can be restored through the strategic introduction of classical correlated noise. This is the first, to the best of our knowledge, experimental evidence, showing that environmental memory effects can substantially enhance phase measurement performance in a squeezing-enhanced optical interferometer under the correlated Gaussian noise, providing valuable insights for practical quantum sensing in noisy environments.