Bloch vector, disclination and exotic quantum holonomy

Atushi Tanaka; Taksu Cheon

doi:10.1016/j.physleta.2015.05.009

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arXiv · 1409.5211

Bloch vector, disclination and exotic quantum holonomy

Atushi Tanaka·Taksu Cheon

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Abstract

A topological formulation of the eigenspace anholonomy, where eigenspaces are interchanged by adiabatic cycles, is introduced. The anholonomy in two-level systems is identified with a disclination of the director (headless vector) of a Bloch vector, which characterizes eigenprojectors. The covering map structure behind the exotic quantum holonomy and the role of the homotopy classification of adiabatic cycles are elucidated. The extensions of this formulation to nonadiabatic cycles and N-level systems are outlined.

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Atushi Tanaka, Taksu Cheon. 2015-03-27. Bloch vector, disclination and exotic quantum holonomy. https://doi.org/10.1016/j.physleta.2015.05.009

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