Chinese Academy of Sciences

Enxue Yun

Shougang Zhang

Qiang Hao

Guobin Liu

Qinglin Li

Yuping Gao

Sihong Gu

Bozhong Tan

The invention relates to a differential detection of double-modulation (DM) CPT method and a system for implementing the method of this invention. The method comprises the following steps: Generating a coherent bichromatic light, in which the polarization and the relative phase are synchronously modulated. The DM light interacts with a quantum resonance system and prepares it into a CPT state. Then the polarization of coherent bichromatic light is switched from circular polarization to linear polarization. After interacting with the CPT state prepared in the previous stage, the constructive and destructive quantum interference occur simultaneously. The polarization of the transmitted light from the quantum resonance system is converted and spatially separated. Then two CPT signals, detected by balanced photodetectors, are observed with constructive and destructive interference respectively. Finally, a differential CPT signal with high signal-to-noise ratio is obtained by subtracting the above-mentioned two CPT signals.

Double-modulation CPT differential detection method and system

The invention relates to a coherent population trapping (CPT) phase modulation and demodulation method and a system for implementing the method of this invention. The method comprises the following steps: Generating a coherent bichromatic light, in which the relative phase between the two frequency components is modulated with proper modulation depth. The phase modulated coherent bichromatic light interacts with a quantum resonance system, and prepares it alternately into two inverted CPT states. Detecting the transmitted light with a photodetector, two inverted dispersive CPT signals in two detection windows are observed. With synchronous phase demodulation, a CPT error signal is obtained, which is used for locking the local oscillator to implement a CPT atomic clock.

CPT phase modulation and demodulation method and system

A device for producing a coherent bi-color light source, including: an array substrate, a first laser tube driven by a first direct current signal, a second laser tube driven by a modulation signal coupled by a microwave signal and a second DC signal, a half wave plate, a birefringent crystal, a first quarter wave plate, a partially reflecting plane mirror, and a second quarter wave plate. The first laser tube and the second laser tube are fixed on the array substrate. The half wave plate, the birefringent crystal, the first quarter wave plate, the partially reflecting plane mirror, and the second quarter wave plate are disposed in sequence in an emission direction of a laser beam emitted by the first laser tube. The second laser tube is disposed opposite to the birefringent crystal.

Device and method for producing coherent bi-color light source

Growing community of inventors

Xi'an, China

Enxue Yun