Cavity stabilization using the weak intrinsic birefringence of dielectric mirrors.

We demonstrate a universal cavity stabilization scheme that exploits the intrinsic birefringence of dielectric multilayer mirrors. Homodyne locking using weak mirror birefringence of even an empty Fabry-Perot-type cavity requires neither frequency modulation nor mixing and allows us to generate an error signal that is comparable to more widely used heterodyne stabilization schemes.