Stablized pump laser with output reflector on polarizing optical fiber

A laser apparatus comprises a pump laser device, and a polarizing optical fiber having a proximal end and a distal end, with the polarizing optical fiber coupled to the pump laser device at the proximal end. At least one output reflector (122) is written on the polarizing optical fiber (120) toward the distal end. Only one polarization mode is supported when a laser beam is transmitted through the polarizing optical fiber (120) from the pump laser device. The laser apparatus may comprise a packaged laser diode (110) having an external cavity, the external cavity comprising an intra-cavity lens (114) and an optical fiber (120) having a grating as output reflector (122). An intra-cavity coiled section (124) of the optical fiber (120) selects one polarisation mode in dependence of the coiling radius.