Continuous phase stabilization and active interferometer control using two modes

TL;DR

This paper introduces a computer-based active interferometer stabilization method using two orthogonal modes, enabling arbitrary phase difference control without beam modulation, with demonstrated stability over days.

Contribution

A novel active stabilization technique employing two modes for phase control that does not require beam modulation, allowing arbitrary phase setting and long-term stability.

Findings

Achieved switching times of 50ms over 0 to 6π radians

Maintained phase stability within 3 degrees for several days

Demonstrated stabilization at 632.8nm wavelength

Abstract

We present a computer-based active interferometer stabilization method that can be set to an arbitrary phase difference and does not rely on modulation of the interfering beams. The scheme utilizes two orthogonal modes propagating through the interferometer with a constant phase difference between them to extract a common phase and generate a linear feedback signal. Switching times of 50ms over a range of 0 to 6 pi radians at 632.8nm are experimentally demonstrated. The phase can be stabilized up to several days to within 3 degrees.