The semiclassical periodic orbit formula is compared with the asymptotic expansion of an exact analytical expression for the trace of the unitary propagator for the quantum standard map. Contributions arising from both real as well as ghost orbits, having complex classical action, have to be included to recover the usual semiclassical fixed point quantization in this limit as was observed by Kuś, Haake, and Delande [Phys. Rev. Lett. 71, 2167 (1993)]. The range of validity of this expansion is derived and a way to extend its range is given.

• Received 30 September 1993

DOI:https://doi.org/10.1103/PhysRevE.49.R4767