Development of a ring laser for polarimetric measurements.

In this paper a method for the measurement of small optical rotations by using a ring laser of special design is described. The proposed instrument could be used, for example, to measure small optical rotations in the near ir, caused by vibration bands of organic substances. The development of the ring laser is discussed. A general theory concerning the states of polarization of a laser with an anisotropic cavity is presented. The dynamic behavior of the state of polarization, as a function of an axial magnetic field, in cavities with linear and circular anisotropies is analyzed. This analysis has led to two methods of polarimetric measurements, which are discussed in detail. The experimental setup is given.