Frequency stabilization of a semiconductor laser using both Rb saturated absorption profiles and double optical feedback systems

Abstract

The precise interferometric systems employed in today's artificial satellites require semiconductor lasers of the highest callibur. But, one particularly large obstacle has stood in the way of their broad application; the stabilization of their oscillation frequencies. While a number of different approaches have been tested, none have provided overall, long-term stability. Most recently, we used a Doppler-free absorption line of Rb atoms with a precision temperature controller and an improved laser mount; in this instance, relative optical frequency stability rated 9.07x10^-13≤&sgr;(2,&tgr;)≤7.54x10^-10, in averaging time for 0.01s≤&tgr;≤23s. By introducing optical feedback, which narrows the laser's linewidth, we obtained improved frequency stability.