Fig. 1. Schematic diagram of the experiment. PPLN, periodically poled lithium niobate crystal; HWP, half-wave plate; QWP, quarter-wave plate; PBS, polarization beam splitter; PD, photodiode; Servo, servo electronics; EOM, electro-optical modulator; MTS, modulation transfer spectroscopy; SAS, saturation absorption spectroscopy; AOM, acousto-optical modulator; GTP, Glan–Taylor prism; LCR, liquid crystal rotator; NDF, neutral density filter.

Fig. 2. (a) Fluorescence and absorption signals of trapped cold atoms when GTP polarizations are parallel; (b) fluorescence and transmitted signal of the probe laser due to the Faraday rotation effect of released cold atoms when GTP polarizations are orthogonal. The horizontal axes represent the loading times relative to the time when MOT is shut off.

Fig. 3. Transmission spectrum of the Faraday atomic filter. The inset shows the frequency reference for the probe laser.

Fig. 4. Dependence of the transmitted signal of probe light and rotation angle on probe laser power with the detuning of 2 MHz. Each data point is an average of 20 measurement results.

Fig. 5. Rotation angle varies with the applied magnetic field with the probe laser power set at 10 µW and a detuning of 2 MHz. Each data point corresponds to 20 times of measurements.