Measurement of Linearly Polarized Light Rotation Applied in Atomic Magnetometer

The measurement of linearly polarized light rotation is the key technique in atomic magnetometer. It influences the sensitivity of atomic magnetometer directly. The basic principle of polarizer beam splitter detecting was analyzed. The ZF7 optical glass and solenoid were used to generate standard small angle based on Faraday effect. The signal of AC rotational angle was extracted by lock-in amplifier. The experiment proved that the method can measure 8×10-7rad small optical rotation. As the linearly polarized light rotation is 20mrad in atomic magnetometer, the signal to noise ratio reaches 25000.