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arXiv · 1510.08645

Quantum adiabatic evolution with energy-degeneracy levels

Qi Zhang
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Abstract

A classical-kind phase-space formalism is developed to address the tiny intrinsic dynamical deviation from what is predicted by Wilczek-Zee theorem during quantum adiabatic evolution on degeneracy levels. In this formalism, the Hilbert space and the aggregate of degenerate eigenstates become the classical-kind phase-space and a high-dimensional subspace in the phase-space, respectively. Compared with the previous same study by a different method, the current result is qualitatively different in that the first-order deviation derived here is always perpendicular to the degeneracy subspace. A tripod scheme Hamiltonian with two degenerate dark states is employed to illustrate the adiabatic deviation with degeneracy levels.

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Qi Zhang. 2015-10-29. Quantum adiabatic evolution with energy-degeneracy levels. https://doi.org/10.1103/physreva.93.012116

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