Quantum Monodromy and Non-concentration near a Closed Semi-Hyperbolic Orbit
arXiv:0803.0697
Abstract
For a large class of semiclassical operators which includes Schrödinger operators on manifolds with boundary, we construct the Quantum Monodromy operator associated to a periodic orbit of the classical flow. Using estimates relating and , we prove semiclassical estimates for small complex perturbations of in the case is semi-hyperbolic. As our main application, we give logarithmic lower bounds on the mass of eigenfunctions away from semi-hyperbolic orbits of the associated classical flow. As a second application of the Monodromy Operator construction, we prove if is an elliptic orbit, then admits quasimodes which are well-localized near .