Optically pumped magnetometers(OPMs)have developed rapidly in the bio-magnetic measurement field,which requires lasers with stable frequency and intensity for high sensitivity.Herein we stabilize a vertical-cavity sur...Optically pumped magnetometers(OPMs)have developed rapidly in the bio-magnetic measurement field,which requires lasers with stable frequency and intensity for high sensitivity.Herein we stabilize a vertical-cavity surface-emitting laser(VCSEL)without any additional setup except for the parts of an OPM.The linewidth of the absorption spectrum as a frequency reference is broadened to 40 GHz owing to pressure broadening.To enhance performance,the VCSEL injection current and temperature are tuned simultaneously using a closed-loop control system.The experiments reveal that the VCSEL frequency stability achieves 2×10^(-7) at an average time of 1 s,and the intensity noise is 1×10^(-6)V/Hz^(1/2) at 1-100 Hz.This approach is useful for suppressing OPM noise without additional sensor probe parts.展开更多
基金supported by the National Key R&D Program of China(No.2018YFB2002405)the National Natural Science Foundation of China(No.61903013)。
文摘Optically pumped magnetometers(OPMs)have developed rapidly in the bio-magnetic measurement field,which requires lasers with stable frequency and intensity for high sensitivity.Herein we stabilize a vertical-cavity surface-emitting laser(VCSEL)without any additional setup except for the parts of an OPM.The linewidth of the absorption spectrum as a frequency reference is broadened to 40 GHz owing to pressure broadening.To enhance performance,the VCSEL injection current and temperature are tuned simultaneously using a closed-loop control system.The experiments reveal that the VCSEL frequency stability achieves 2×10^(-7) at an average time of 1 s,and the intensity noise is 1×10^(-6)V/Hz^(1/2) at 1-100 Hz.This approach is useful for suppressing OPM noise without additional sensor probe parts.
