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An open source digital servo for atomic, molecular, and optical physics experiments



David R. Leibrandt, Jason Heidecker


We describe a general purpose digital servo optimized for feedback control of lasers in atomic, molecular, and optical (AMO) physics experiments. The servo is capable of feedback bandwidths up to roughly 1~MHz; loop filter shapes up to fifth order; multiple-input, multiple-output control; and automatic lock acquisition. The configuration of the servo is controlled via a graphical user interface, which also provides a rudimentary software oscilloscope and tools for measurement of system transfer functions. We illustrate the functionality of the digital servo by describing its use in two example scenarios: frequency control of the laser used to probe the narrow clock transition of 27Al+ in an optical atomic clock, and length control of a cavity used for resonant frequency doubling of a laser.
Review of Scientific Instruments


control systems, digital signal processing, servo devices


Leibrandt, D. and Heidecker, J. (2015), An open source digital servo for atomic, molecular, and optical physics experiments, Review of Scientific Instruments, [online], (Accessed April 14, 2024)
Created December 30, 2015, Updated August 10, 2018