Asymmetric Barriers Yield Symmetrical Quantum Tunneling, Researchers Find

Researchers from Max Planck Institute for Nuclear Physics and Tulane University have demonstrated that quantum particles tunneling through an asymmetrical barrier experience identical reflection and transmission probabilities, a phenomenon first observed by Landau and Lifshitz and later proven generally by Shegelski and Sample. This observation challenges the expectation that asymmetry would differentiate outcomes based on the direction of incidence. Time-dependent Wigner-function simulations reveal the origin of directional control lies not in the transmitted current, but within the barrier itself; a sharp edge generates significantly more under-barrier negative-energy population than a smooth one. However,…