Injection locking a Q-switched standing-wave alexandrite laser with a frequency-stabilized diode laser

Abstract

An AlGaAs diode laser at 760 nm is frequency stabilized to a molecular-oxygen absorption line and is used to injection lock a Q-switched alexandrite laser, which will be used as a lidar source in the remote sensing of atmospheric pressure and temperature. The diode laser operates nominally at 761 nm. Temperature tuning to the absorption feature of interest is accomplished by externally adjusting a temperature-bias voltage to the diode controller. Active frequency stabilization is achieved through photoacoustic feedback by frequency dithering the diode through an oxygen cell. Stabilization to less than 15 MHz has been reported. Successful injection locking of the broadband standingwave alexandrite laser has resulted in a linewidth of less than 500 MHz in an 85 ns pulse, 20 mJ/pulse, 5 pps.