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Precise coupling terms in adiabatic quantum evolution: The generic case

Volker Betz·Stefan Teufel
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Abstract

For multi-level time-dependent quantum systems one can construct superadiabatic representations in which the coupling between separated levels is exponentially small in the adiabatic limit. Based on results from [BeTe1] for special Hamiltonians we explicitly determine the asymptotic behavior of the exponentially small coupling term for generic two-state systems with real-symmetric Hamiltonian. The superadiabatic coupling term takes a universal form and depends only on the location and the strength of the complex singularities of the adiabatic coupling function. As shown in [BeTe1], first order perturbation theory in the superadiabatic representation then allows to describe the time-development of exponentially small adiabatic transitions and thus to rigorously confirm Michael Berry's [Ber] predictions on the universal form of adiabatic transition histories.

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Volker Betz, Stefan Teufel. 2004-11-29. Precise coupling terms in adiabatic quantum evolution: The generic case. https://doi.org/10.1007/s00220-005-1419-1

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