【摘 要】
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Heterodyne detectors as phase-insensitive[PI]devices have found important applications in precision measurements such as space-based gravitational-wave[GW]observation.However,the output signal of a Pl heterodyne detector is supposed to suffer from signal-
【机 构】
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Hubei Key Laboratory of Modern Manufacturing Quality Engineering,School of Mechanical Engineering,Hu
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Heterodyne detectors as phase-insensitive[PI]devices have found important applications in precision measurements such as space-based gravitational-wave[GW]observation.However,the output signal of a Pl heterodyne detector is supposed to suffer from signal-to-noise ratio[SNR]degradation due to image band vacuum and imperfect quantum efficiency.Here,we show that the SNR degradation can be overcome when the image band vacuum is quantum correlated with the input signal.We calculate the noise figure of the detector and prove the feasibility of heterodyne detection with enhanced noise per-formance through quantum correlation.This work should be of great interest to ongoing space-borne GW signal searching experiments.
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