Highly sensitive intensity-type polarization chiral sensor with reference light

Abstract

Optical rotation is a special phenomenon in which the plane of polarization of polarized light is rotated after passing through a chiral medium. This work first, to our knowledge, presents and optimizes a polarization chiral sensor with a reference light on the basis of a weak measurement light path. The influences of phase shift and polarization angle difference on sensitivity were theoretically optimized and verified experimentally. The introduction of a reference light further reduced the impact of light source fluctuations on the detection signal, improving the signal-to-noise ratio and reducing the optical rotation resolution to 2 × 10−5 rad. This method has the characteristics of low cost, high sensitivity, and real-time rapid detection, making it potentially applicable in the field of chemical analysis, such as chiral molecule detection.