Analysis and suppression of thermal effect of an ultra-stable laser interferometer for space-based gravitational waves detection

In this paper,we present a suppression method for the thermal drift of an ultra-stable laser interferometer.The detailed analysis on the Michelson interferometer indicates that the change in optical path length induced by temperature variation can be effectively reduced by choosing proper thickness and/or incident angle of a compensator.Taking the optical bench of the Laser Interferometer Space Antenna Pathfinder as an example,we analyze the optical bench model with a compensator and show that the temperature coefficient of this laser interferometer can be reduced down to 1 pm/K with an incident angle of 0.267828 rad.The method presented in this paper can be used in the design of ultra-stable laser interferometers,especially for space-based gravitational waves detection.