Polarization-switchable Q-switched DFB fiber laser

A polarization switchable Q-switched distributed feedback (DFB) fiber laser is presented. This what we believe to be a new Q-switching method allows one to obtain linearly polarized laser emission in either x or y direction. The principle of this method is based on a variable birefringent phase shift induced by a lateral stress applied at a precise location along a fiber Bragg grating by a specially designed hyper-elastic device. A piezoelectric actuator controls the amount of stress delivered to the fiber, thus allowing a precise and rapid tuning of the cavity Q-factor.