Physical Review Letters
Exact and Quasiclassical Fredholm Solutions of Quantum Billiards
Bertrand Georgeot, R. E. Prange
Abstract
Quantum billiards are much studied as perhaps the simplest case which presents the central difficulty that the quasiclassical approximation is expressed as a divergent series. We find here, using the Fredholm method, an exact Green's function for billiards expressed as a ratio of absolutely convergent series. We make the quasiclassical approximation to this ratio. The method provides a convergence argument for previous results and an extension of results obtained for the spectrum to the full Green's function.