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Landau-Zener problem in a three-level neutrino system with non-linear time dependence

P. Keränen·J. Maalampi·M. Myyryläinen·J. Riittinen
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Abstract

We consider the level-crossing problem in a three-level system with non-linearly time-varying Hamiltonian (time-dependence $t^{-3}$). We study the validity of the so-called independent crossing approximation in the Landau-Zener model by making comparison with results obtained numerically in density matrix approach. We also demonstrate the failure of the so-called "nearest zero" approximation of the Landau-Zener level-crossing probability integral.

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P. Keränen, J. Maalampi, M. Myyryläinen, J. Riittinen. 2007-02-01. Landau-Zener problem in a three-level neutrino system with non-linear time dependence. https://doi.org/10.1103/physrevd.75.033006

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