Semiclassical quantization by Padé approximant to periodic orbit sums

¹ Institut für Theoretische Physik und Synergetik, Universität Stuttgart D-70550 Stuttgart, Germany
² Department of Chemistry, University of Southern California Los Angeles, CA 90089, USA

Received: 27 May 1999
Accepted: 7 September 1999

Abstract

Periodic orbit quantization requires an analytic continuation of non-convergent semiclassical trace formulae. We propose a method for semiclassical quantization based upon the Padé approximant to the periodic orbit sums. The Padé approximant allows the re-summation of the typically exponentially divergent periodic orbit terms. The technique does not depend on the existence of a symbolic dynamics and can be applied to both bound and open systems. Numerical results are presented for two different systems with chaotic and regular classical dynamics, viz. the three-disk scattering system and the circle billiard.