Active intensity noise suppression for a broadband mid-infrared laser source

The D2-125 Reconfigurable Servo was originally designed to lock a cw laser to an error signal such as a narrow atomic absorption line or a high-finesse cavity.  But Marinus Huber from the Ludwig-Maximilians-University and the Max-Planck-Institute for Quantum Optics and his colleagues have also used it to control the intensity of an ultrafast mid-ir laser.  Through feedback to an aom, they were able to reduce the intensity noise by as much as a factor of 20 over a bandwidth of 1 Hz to 100 kHz.

A paper describing the technique and performance of the system was published in Optics Express (Vol. 25, No. 19, pg. 22499, 18 Sep 2017).