Wideband Frequency Noise Reduction In Laser Diodes Using FM Sideband Technique And Electronical Feedback

摘要

It has been found that acousto-optical modulator (AOM) operating in a Raman-Nath diffraction mode can be used as an external phase modulator in Pound-Drever FM sideband technique converting the single mode laser diode input into a pure frequency-modulated (FM) spatially separated optical spectrum. With the use of Pound-Drever FM sideband technique and negative electrical feedback, wide-bandwidth frequency noise suppression and stable frequency locking of the external cavity laser diodes (ECLD) to the sub-Doppler resonances within caesium D_2 spectral line is achievable.