Precision Controlling of Frequency Difference for Elastic-Stress Birefringence He--Ne Dual-Frequency Lasers

Birefringence-Zeeman dual frequency lasers are capable of producing frequency difference from several kilohertz to hundreds of megahertz, but the precision of giving and stabilizing of the beat frequency still needs improvement to the range of ±200kHz. We design a new elastic force-exerting device comprised of the bottom part, two arms and two pieces of force-exerting sheets. The frequency difference smoothly tuning is realized with this device in a large range of 2MHz to 20MHz. Power-balance frequency stabilization system is used to investigate characters of the temperature, frequency difference and laser power. The precision of the frequency difference has reach up to ±100kHz after system temperature balance. Analyses of the laser frequency difference and power character are carried out.