Characteristics and applications of birefringent-fiber Kerr-couplers

We consider the effects of the pump power and the interaction length on the efficiency of polarization coupling induced by the optical Kerr effect in high-birefringence fibers. An efficiency of up to 100% is predicted for suitable combinations of the length and the strength of the birefringence grating in the fiber. The device is rapidly tunable, highly selective in wavelength, and independent of any thermal drift in the fiber. Potential applications include real-time tuning in wavelength-division demultiplexers, wavelength selection in optical spectrum analyzers, and band rejection in tunable notch filters.