Zeeman laser interferometer errors for high-precision measurements

Abstract

We present a theoretical analysis of the errors of a Zeeman laser interferometer due to the nonorthogonally elliptic polarizations of laser modes. The polarizations make the measured Doppler frequency-shift signal become a modulated and nonharmonic signal and make the phase shift unstable and nonrepeatable when the signal is measured by a phasemeter. If the orthogonality error between two major axes of the laser polarizations is 6°, the relative errors of the phasemeter output will exceed 200% when the measured phase shift is changed from −16.2° to +3.5°. We also introduce a way to eliminate the errors.