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Switching of Geometric Phase in Degenerate Systems

Asher Yahalom·Robert Englman
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Abstract

The geometric and open path phases of a four-state system subject to time varying cyclic potentials are computed from the Schr\"{o}dinger equation. Fast oscillations are found in the non-adiabatic case. For parameter values such that the system possesses degenerate levels, the geometric phase becomes anomalous, undergoing a sign switch. A physical system to which the results apply is a molecular dimer with two interacting electrons. Additionally, the sudden switching of the geometric phase promises to be an efficient control in two-qubit quantum computing.

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Asher Yahalom, Robert Englman. 2000-07-12. Switching of Geometric Phase in Degenerate Systems. https://doi.org/10.1016/s0375-9601(00)00425-4

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