Chiral liquids rotate the plane of polarization of linearly polarized light and are therefore optically active. Here we show that optical rotation can be observed in the frequency domain. A chiral liquid introduced in a fiber-loop ring resonator that supports left and right circularly polarized modes gives rise to relative frequency shifts that are a direct measure of the liquid’s circular birefringence and hence of its optical activity. The effect is in principle not diminished if the circumference of the ring is reduced. The technique is similarly applicable to refractive index and linear birefringence measurements.
© 2006 Optical Society of America
Instrumentation, Measurement, and Metrology
Original Manuscript: September 22, 2005
Revised Manuscript: November 11, 2005
Manuscript Accepted: November 12, 2005
Frank Vollmer and Peer Fischer, "Ring-resonator-based frequency-domain optical activity measurements of a chiral liquid," Opt. Lett. 31, 453-455 (2006)