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arXiv · hep-th/9701086

The SU(2) instanton and the adiabatic evolution of two Kramers doublets

M. T. Johnsson·I. J. R. Aitchison
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Abstract

The adiabatic evolution of two doubly-degenerate (Kramers) levels is considered. The general five-parameter Hamiltonian describing the system is obtained and shown to be equivalent to one used in the $Γ_8 \otimes(τ_2\oplusε)$ Jahn-Teller system. It is shown explicitly that the resulting SU(2) non-Abelian geometric vector potential is that of the (SO(5) symmetric) SU(2) instanton. Various forms of the potentials are discussed.

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M. T. Johnsson, I. J. R. Aitchison. 1997-01-17. The SU(2) instanton and the adiabatic evolution of two Kramers doublets. https://doi.org/10.1088/0305-4470%2F30%2F6%2F029

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