A Digital Phase Lock Loop for an External Cavity Diode Laser

作者:Wang Xiao-Long; Tao Tian-Jiong; Cheng Bing; Wu Bin; Xu Yun-Fei; Wang Zhao-Ying; Lin Qiang*
来源:Chinese Physics Letters, 2011, 28(8): 084214.
DOI:10.1088/0256-307X/28/8/084214

摘要

A digital optical phase lock loop (OPLL) is implemented to synchronize the frequency and phase between two external cavity diode lasers (ECDL), generating Raman pulses for atom interferometry. The setup involves all-digital phase detection and a programmable digital proportional-integral-derivative (PID) loop in locking. The lock generates a narrow beat-note linewidth below 1Hz and low phase-noise of 0.03 rad(2) between the master and slave ECDLs. The lock proves to be stable and robust, and all the locking parameters can be set and optimized on a computer interface with convenience, making the lock adaptable to various setups of laser systems.