Effects of geometrical ray chaos on the electromagnetic eigenmodes of a gradient index optical cavity.

Electromagnetic analogies of quantum chaos are investigated in two-dimensional optical cavities which have reflective surfaces and contain a gradient refractive index medium. As the shape of the cavity is transformed continuously from a rectangle to a parallelogram, the geometrical ray paths undergo a transition from stable to chaotic dynamics. In the chaotic regime, the spectral statistics of the cavity are accurately described by random matrix theory. In addition, the electromagnetic mode spectrum of the cavity is modulated by both real and ghost periodic ray paths. These paths also "scar" the electric field intensity distributions of regular subsets of cavity eigenmodes.