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arXiv · 1004.0987

Two-dimensional tunneling in a SQUID

B. Ivlev
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Abstract

Traditionally quantum tunneling in a static SQUID is studied on the basis of a classical trajectory in imaginary time under a two-dimensional potential barrier. The trajectory connects a potential well and an outer region crossing their borders in perpendicular directions. In contrast to that main-path mechanism, a wide set of trajectories with components tangent to the border of the well can constitute an alternative mechanism of multi-path tunneling. The phenomenon is essentially non-one-dimensional. Continuously distributed paths under the barrier result in enhancement of tunneling probability. A type of tunneling mechanism (main-path or multi-path) depends on character of a state in the potential well prior to tunneling.

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B. Ivlev. 2010-04-07. Two-dimensional tunneling in a SQUID. https://doi.org/10.1103/physrevb.82.184513

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