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arXiv · 1609.01418

Landau-Zener-Stueckelberg physics with a singular continuum of states

D. M. Basko
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Abstract

This work addresses the dynamical quantum problem of a driven discrete energy level coupled to a semi-infinite continuum whose density of states has a square-root-type singularity, such as states of a free particle in one dimension or quasiparticle states in a BCS superconductor. The system dynamics is strongly affected by the quantum-mechanical repulsion between the discrete level and the singularity, which gives rise to a bound state, suppresses the decay into the continuum, and can produce Stueckelberg oscillations. This quantum coherence effect may limit the performance of mesoscopic superconducting devices, such as quantum electron turnstile.

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D. M. Basko. 2016-12-16. Landau-Zener-Stueckelberg physics with a singular continuum of states. https://doi.org/10.1103/physrevlett.118.016805

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