Controlling the Emission Spectrum of a Laser with Anisotropic Mirrors

Anisotropic lasers mirrors with adjusted birefringence and diattenuation can produce degenerate polarization eigenstates that eliminate dual polarization emission in a standing wave resonator. Such laser mirrors also produce orthogonally-polarized counter-propagating waves, which eliminate spatial hole burning and promote single longitudinal mode emission. These mirrors can be obtained by depositing nanostructured thin films on top of conventional laser mirrors using physical vapor deposition on inclined substrates, offering single frequency emission of compact microchip ceramic lasers.