MANY-PATH INTERFERENCE AND TOPOLOGICALLY SUPPRESSED TUNNELING

Quantum interference is studied for a charged particle on a multiply c onnected configuration space. The holes of the space are assumed to ac commodate independent magnetic fluxes. As follows from an instanton ca lculation, tunneling of the particle is suppressed completely in such a geometry for appropriately chosen field strengths. This set of value s defines an algebraic variety in parameter space, not a manifold. The quenching persists even if the geometric symmetry of the system is br oken. Aharonov-Bohm-type experiments and mesoscopic tunneling devices are natural candidates to observe many-path interference.