Phase sensitive optical rotation measurement using the common-path heterodyne interferometry and a half-wave plate at a specific azimuth angle

Abstract

We proposed a new method for small optical rotation measurement. The method is based on the use of a half-wave plate and the high-stability common-path heterodyne interferometry. When the azimuth angle is at 22.5 ° of a half-wave plate, the phase has a distinct change caused by the small polarization rotation of the test beam. The optical rotation can be obtained from the relationship between the phase and the azimuth angle of the wave plate. The resolution of polarization rotation measurement can achieve 1.6 × 10 −5 degree/mm and the detection sensitivity on circular birefringence of glucose-water solution can be up to δ|n r − n l | = 5.6 × 10 −11 .