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Geometric Phase of Three-level Systems in Interferometry

Barry C. Sanders·Hubert de Guise·Stephen D. Bartlett·Weiping Zhang
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Abstract

We present the first scheme for producing and measuring an Abelian geometric phase shift in a three-level system where states are invariant under a non-Abelian group. In contrast to existing experiments and proposals for experiments, based on U(1)-invariant states, our scheme geodesically evolves U(2)-invariant states in a four-dimensional SU(3)/U(2) space and is physically realized via a three-channel optical interferometer.

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Barry C. Sanders, Hubert de Guise, Stephen D. Bartlett, Weiping Zhang. 2001-02-01. Geometric Phase of Three-level Systems in Interferometry. https://doi.org/10.1103/physrevlett.86.369

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