10-Hertz quantum light source generation on the cesium D2 line using single photon modulation

TL;DR

This paper reports the first experimental generation of low-frequency quadrature squeezing resonating on the cesium D2 line at 10 Hz, with a maximum squeezing of 5.57 dB, enabling advancements in quantum metrology and related fields.

Contribution

It introduces a novel method for generating low-frequency quantum light on the cesium D2 line with single-photon modulation locking to control squeezing angle and suppress laser noise.

Findings

Achieved quadrature squeezing down to 10 Hz on the cesium D2 line.

Maximum squeezing of 5.57 dB in the audio frequency band.

System operates steadily for hours, suitable for practical applications.

Abstract

Generation of quantum light source is a promising technique to overcome the standard quantum limit in precision measurement. Here, we demonstrate an experimental generation of quadrature squeezing resonating on the cesium D2 line down to 10 Hz for the first time. The maximum squeezing in audio frequency band is 5.57 dB. Moreover, we have presented a single-photon modulation locking to control the squeezing angle, while effectively suppressing the influence of laser noise on low-frequency squeezing. The whole system operates steadily for hours. The generated low-frequency quantum light source can be applied in quantum metrology,light-matter interaction investigation and quantum memory in the audio frequency band and even below.