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
We report the recent progress of our pulsed optically pumped（POP） vapor cell rubidium clock with dispersive detection.A new compact physics package is made.A rubidium cell with a high precision buffer gases mixing r...We report the recent progress of our pulsed optically pumped（POP） vapor cell rubidium clock with dispersive detection.A new compact physics package is made.A rubidium cell with a high precision buffer gases mixing ratio is obtained,and the temperature controlling system is renovated to reduce fractional frequency sensitivity to temperature variation.The resolution of the servo control voltage is also optimized.With these improvements,a clock frequency stability of 3.53×10-13 at 1s is obtained,and a fractional frequency stability of 4.91×10-15 is achieved at an average time of τ=2000 s.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.
基金supported by the National Natural Science Foundation of China under Grant Nos.91536220 and 11504393
文摘We report the recent progress of our pulsed optically pumped（POP） vapor cell rubidium clock with dispersive detection.A new compact physics package is made.A rubidium cell with a high precision buffer gases mixing ratio is obtained,and the temperature controlling system is renovated to reduce fractional frequency sensitivity to temperature variation.The resolution of the servo control voltage is also optimized.With these improvements,a clock frequency stability of 3.53×10-13 at 1s is obtained,and a fractional frequency stability of 4.91×10-15 is achieved at an average time of τ=2000 s.
