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arXiv · 0705.3155

Observation of Topological and Parity-dependent Phase of $m=0$ Spin States

Koji Usami·Mikio Kozuma
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Abstract

A Ramsey interrogation scheme was used to measure the phase shift of laser-cooled $^{87}$Rb clock-transition pseudospins arising as a result of a reversal of a bias magnetic field, i.e., $\textbf{B} \to -\textbf{B}$, during the interrogation. While no phase shift occurred when the reversal was sudden, the Ramsey fringes were shifted by a factor of $π$ when the reversal was adiabatic. We thus verified the prediction that the spin states $|F,m=0 >$ acquire a purely topological and parity-dependent phase factor of $(-1)^{F}$ as a result of $\textbf{B} \to -\textbf{B}$.

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Koji Usami, Mikio Kozuma. 2007-10-09. Observation of Topological and Parity-dependent Phase of $m=0$ Spin States. https://doi.org/10.1103/physrevlett.99.140404

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