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arXiv · 2401.07946

Manifestation of the Berry connection in chiral lattice systems

Francesco Di Colandrea·Nazanin Dehghan·Filippo Cardano·Alessio D'Errico·Ebrahim Karimi
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Abstract

The Aharonov-Bohm effect is a physical phenomenon where the vector potential induces a phase shift of electron wavepackets in regions with zero magnetic fields. It is often referred to as evidence for the physical reality of the vector potential. A similar effect can be observed in solid-state systems, where the Berry connection can influence electron dynamics. Here, we show that in chiral-symmetric processes the Berry connection determines an observable effect on the mean chiral displacement of delocalized wavefunctions. This finding is supported by a photonic experiment realizing a topological quantum walk, and demonstrates a new effect that can be attributed directly to the presence of a gauge field.

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Francesco Di Colandrea, Nazanin Dehghan, Filippo Cardano, Alessio D'Errico, Ebrahim Karimi. 2024-01-15. Manifestation of the Berry connection in chiral lattice systems. https://doi.org/10.1038/s42005-024-01746-y

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