Signature of non-Newtonian orbits in ray-splitting cavities

Ray splitting is a universal phenomenon that occurs in all wave systems with sharp interfaces. A key consequence of ray splitting is the occurrence of non-Newtonian periodic orbits whose presence can he revealed in the oscillating part of the density of states. We use thin dielectric-and metal-loaded microwave cavities to identify experimentally the signature of non-Newtonian periodic orbits caused by ray splitting at sharp interfaces and corroborate all our experimental results with detailed numerical computations and semiclassical theory. For two-dimensional ray-splitting problems the electromagnetic Helmholtz and quantal Schrodinger equations are equivalent. Thus our results are directly relevant to quantum chaos studies.