New possibilities for measuring optical nonreciprocity in a solid-state ring laser

New methods are proposed for measuring the amplitude and frequency nonreciprocity of the ring resonator in a solid-state ring laser operating under self-modulation conditions. The amplitude nonreciprocity can be found from measurements of the phase difference between the self-oscillations in the intensities of the counterpropagating waves. Equations are derived which relate the amplitude and frequency nonreciprocity with certain parameters of the self-oscillations which can be measured. The possibility of determining the frequency nonreciprocity through a comparison of two signals, namely, the intensity of one of the generated modes and the signal of the photomixing two counterpropagating waves, is discussed.