Polarization effects in a high-birefringence elliptical fiber laser with aBragg grating in a low-birefringence fiber

The polarization characteristics of a fiber laser cavity that combines a hi gh-birefringence Er3+-doped elliptical core fiber with a Bragg grating fabr icated in a low-birefringence (Low-Bi) fiber are studied. It is shown that, bg use of an adequate length of Low-Bi fiber and an intracavity polarizati on controller, the dependence of the fiber laser's state of polarization on the pump's state of polarization-can he altered. This fiber laser cavity d esign allows for the realization of a double-frequency, orthogonally polari zed single-mode fiber laser source insensitive to the polarization paramete rs of the pump source. (C) 2000 Optical Society of America.