‘‘Quantum’’ chaos in billiards studied by microwave absorption

Abstract
The eigenfrequencies of resonance cavities shaped as stadium or Sinai billiards are determined by microwave absorption. In the applied frequency range 0–18.74 GHz the used cavities can be considered as two dimensional. For this case quantum-mechanical and electromagnetic boundary conditions are equivalent, and the resonance spectrum of the cavity is, if properly normalized, identical with the quantum-mechanical eigenvalue spectrum. Spectra, containing up to a thousand eigenfrequencies, are obtained within minutes. Statistical properties of the spectra as well as their correlation with classical periodic orbits are discussed.