A Simple Dual-Wavelength Frequency-Locked Laser Device Based on Modulation Transfer Spectroscopy

In order to obtain a stable frequency light source that can be applied to two-color interferometry, this paper locks a dual-wavelength frequency-doubled laser onto the <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">127</sup>I<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> R(56)32-0: a10 based on modulation transfer spectroscopy. From the amplitude of the error signal, the peak to peak frequency fluctuation of the system within 8 hours is about 0.36 MHz, with a relative frequency fluctuation of 6.4 x 10-<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">10</sup>. In addition, a wavelength meter was used to monitor the wavelength drift before and after that frequency was locked, indicating that the system has good frequency stability. The optical power required for the frequency-locked system is only 0.4mW. On the basis of meeting the frequency stability requirements for interferometric measurement, the remaining majority of the optical power will be used for subsequent interferometric measurement experiments.