Abstract: The present disclosure provides a dispersion measurement device and method based on a Franson second-order quantum interference technology. The device includes: an energy-time entangled twin-photon source configured to generate a plurality of optical signals, where the optical signals each include a signal photon and an idle photon; a polarization splitter configured to split the signal photon and the idle photon, and enable the signal photon to pass through a to-be-measured dispersive medium, such that a correlation time processing module records, under a width of a coincidence measurement integration window, first time of the idle photon arriving at a first single-photon detector, and second time of the signal photon arriving at a second single-photon detector, and obtains a twin-photon conference time width based on the first time and the second time; and a processing module.

Abstract: Provided are an atomic beam magnetic resonance method and system based on combined separated oscillatory fields.

Abstract: An optically pumped atomic beam apparatus based on curved four conductors includes a vacuum chamber; and a magnetic shielding chamber, a beam source device, a curved four-conductor static magnetic field generation structure, a microwave cavity, and a fluorescence collection device are disposed in the vacuum chamber. The curved four-conductor static magnetic field generation structure is composed of the curved four conductors with same shapes and sizes, and the curved four conductors are symmetrically arranged by taking an atomic beam as a center axis; a middle portion of each of the curved four conductors is a straight section, and two end portions of each of the curved four conductors are two curved sections bent towards the atomic beam; and a rectangle is formed by intersecting any plane perpendicular to the atomic beam with the curved four conductors, and a length-width ratio of each rectangle is the same.

Abstract: Provided are a method and a system for bichromatic laser frequency stabilization based on differential detection of coexisting Lamb-dips and Lamb-peaks under multiple interactions. Based on multiple interactions between a multichromatic laser beam and a quantum resonance system in a Doppler-free configuration, and by setting the relative polarization directions and Raman phases between the pump and probe light which propagate in opposite directions and overlap in space, Lamb-dips and Lamb-peaks signals are generated; and by subtracting one from the other, a Doppler-free quantum resonance signal with high rejection of Doppler-broadening background and common-mode noise is obtained. The Doppler-free quantum resonance signal obtained in the present application has improved contrast and signal-to-noise ratio, and maintained narrow linewidth, making it applicable for precision spectral measurement as well as for laser frequency locking.

Abstract: A method for correcting an orbit error of common-view time comparison of a space station, comprising five parts, i.e., determination of moments when two stations can simultaneously view the space station, calculation of projection coefficients of the orbit error, calculation of a three-dimensional orbit error vector set, calculation of a set of projection differences of the orbit error in line-of-sight directions of the two stations, and threshold decision. By means of calculation of the five parts, the maximum influence quantity of the orbit error on a common-view time comparison result is obtained, observation moments with the maximum influence quantity exceeding a decision threshold are eliminated, and observation points with the influence of the orbit error on the common-view time comparison less than the decision threshold are reserved.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: Provided is an electro-optical phase modulation system, including: an electro-optical crystal, a radio frequency circuit and a light source, light incident surface of the electro-optical crystal is in parallel with light exit surface, upper electrode surface thereof is in parallel with lower electrode surface, and an angle between light incident surface and upper electrode surface is Brewster angle; two electrodes of radio frequency circuit are connected to upper and lower electrode surfaces respectively, for transmitting radio frequency signals to upper and lower electrode surfaces, so that an electric filed, direction of which is perpendicular to upper electrode surface, is formed between upper and lower electrode surfaces; light source is located at a side of light incident surface, and incidence angle of beams from light source with respect to light incident surface is Brewster angle. The system is used to reduce residual amplitude modulation, and increase accuracy of phase modulation.