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arXiv · 0810.2912

Entanglement, Berry Phases, and Level Crossings for the Atomic Breit-Rabi Hamiltonian

Sangchul Oh·Zhen Huang·Uri Peskin·Sabre Kais
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Abstract

The relation between level crossings, entanglement, and Berry phases is investigated for the Breit-Rabi Hamiltonian of hydrogen and sodium atoms, describing a hyperfine interaction of electron and nuclear spins in a magnetic field. It is shown that the entanglement between nuclear and electron spins is maximum at avoided crossings. An entangled state encircling avoided crossings acquires a marginal Berry phase of a subsystem like an instantaneous eigenstate moving around real crossings accumulates a Berry phase. Especially, the nodal points of a marginal Berry phase correspond to the avoided crossing points.

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Sangchul Oh, Zhen Huang, Uri Peskin, Sabre Kais. 2008-10-16. Entanglement, Berry Phases, and Level Crossings for the Atomic Breit-Rabi Hamiltonian. https://doi.org/10.1103/physreva.78.062106

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