Optimal design for spectral narrowing and fast frequency sweep of an interferometer-stabilized laser

摘要

Self-heterodyne fiber interferometers have been shown to be capable of stabilizing lasers to ultra-narrow linewidths and present an excellent alternative to high-finesse cavities for frequency stabilization. In addition to suppressing frequency noise, these devices are highly tunable and can be manipulated to produce high-speed frequency sweeps over the entire range of the laser. We present an analytic approach for choosing a delay-line length for both optimal noise suppression and highest in-loop frequency sweep rate. Based on this model, we stabilize an extended cavity diode laser to a fiber Michelson interferometer and demonstrate a linewidth of 700 Hz over millisecond timescales while also allowing for a frequency scan rate of 1 THz/ s. We independently measure the maximum deviation from linearity of the sweep to be only 100 kHz. (C) 2019 Optical Society of America