A Faraday laser with frequency automatically trace to Cs-D2 transition

We constructed an 852nm Faraday laser using a Faraday anomalous dispersion optical filter (FADOF) of cesium as the frequency-selective element. Utilizing the Faraday effect, under a magnetic field strength of 1000G, the center frequency of the FADOF transmission spectrum is optimized to correspond with the wavelength of the Cs transition by precisely adjusting the temperature of the Cs vapor cell. When the cell temperature is 61℃, the peak transmission frequency of FADOF is the same as the 6S_1/2(F=4)-6P_3/2 transition frequency of cesium atoms. The transmission spectrum of FADOF has a maximum transmittance of 80% and a Doppler-broadened transmittance bandwidth of 2.25GHz. The output wavelength is stabilized at 852.356nm within the transmission frequency region. When the laser diode (LD) current and temperature change from 70 to 150mA and 15 to 30℃, its wavelength fluctuations are within 2pm and 1pm, respectively. In summary, we investigate a Faraday laser based on a FADOF with a specific parameter as the frequency-selective element, whose output wavelength can be automatically traced to the atomic transition. Therefore, the Faraday laser can be widely used due to its excellent robustness to fluctuating diode parameters.