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Observation of off-diagonal geometric phase in polarized neutron interferometer experiments

Y. Hasegawa·R. Loidl·G. Badurek·M. Baron·N. Manini·F. Pistolesi·H. Rauch
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Abstract

Off-diagonal geometric phases acquired in the evolution of a spin-1/2 system have been investigated by means of a polarized neutron interferometer. Final counts with and without polarization analysis enable us to observe simultaneously the off-diagonal and diagonal geometric phases in two detectors. We have quantitatively measured the off-diagonal geometric phase for noncyclic evolutions, confirming the theoretical predictions. We discuss the significance of our experiment in terms of geometric phases (both diagonal and off-diagonal) and in terms of the quantum erasing phenomenon.

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Y. Hasegawa, R. Loidl, G. Badurek, M. Baron, N. Manini, F. Pistolesi, H. Rauch. 2002-01-14. Observation of off-diagonal geometric phase in polarized neutron interferometer experiments. https://doi.org/10.1103/physreva.65.052111

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