QUANTUM CORRECTIONS TO THE CONDUCTIVITY AND PERIODIC-ORBITS - INTEGRABLE SYSTEMS

We extend the recently developed semiclassical theory for the conducti vity to periodic semiconductor structures whose classical dynamics is integrable; We find that the conductivity of integrable systems exhibi ts quantum oscillations as function of magnetic field and Fermi energy which are closely related to both the Shubnikov-de Haas oscillations and the oscillations observed in the conductivity of antidot lattices. A general expression for the quantum oscillations is derived which is analogous to the Berry-Tabor formula for the spectral density of inte grable systems.