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arXiv · 2010.15159

Non-abelian Thouless pumping in a photonic lattice

Valentina Brosco·Laura Pilozzi·Rosario Fazio·Claudio Conti
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Abstract

Non-abelian gauge fields emerge naturally in the description of adiabatically evolving quantum systems having degenerate levels. Here we show that they also play a role in Thouless pumping in the presence of degenerate bands. To this end we consider a photonic Lieb lattice having two degenerate non-dispersive modes and we show that, when the lattice parameters are slowly modulated, the propagation of the photons bear the fingerprints of the underlying non-abelian gauge structure. The non-dispersive character of the bands enables a high degree of control on photon propagation. Our work paves the way to the generation and detection of non-abelian gauge fields in photonic and optical lattices.

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Valentina Brosco, Laura Pilozzi, Rosario Fazio, Claudio Conti. 2020-10-28. Non-abelian Thouless pumping in a photonic lattice. https://doi.org/10.1103/physreva.103.063518

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