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arXiv · hep-th/9704062

Duality in potential curve crossing: Application to quantum coherence

Kazuo Fujikawa·Hiroshi Suzuki
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Abstract

A field dependent $su(2)$ gauge transformation connects between the adiabatic and diabatic pictures in the (Landau-Zener-Stueckelberg) potential curve crossing problem. It is pointed out that weak and strong potential curve crossing interactions are interchanged under this transformation, and thus realizing a naive strong and weak duality. A reliable perturbation theory should thus be formulated in the both limits of weak and strong interactions. In fact, main characteristics of the potential crossing phenomena such as the Landau-Zener formula including its numerical coefficient are well-described by simple (time-independent) perturbation theory without referring to Stokes phenomena. We also show that quantum coherence in a double well potential is generally suppressed by the effect of potential curve crossing, which is analogous to the effect of Ohmic dissipation on quantum coherence.

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Kazuo Fujikawa, Hiroshi Suzuki. 1997-07-23. Duality in potential curve crossing: Application to quantum coherence. https://doi.org/10.1103/physreva.56.3436

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