Topological edge states with ultracold atoms carrying orbital angular momentum in a diamond chain

G. Pelegrí; A. M. Marques; R. G. Dias; A. J. Daley; V. Ahufinger; J. Mompart

doi:10.1103/physreva.99.023612

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arXiv · 1807.07533

Topological edge states with ultracold atoms carrying orbital angular momentum in a diamond chain

G. Pelegrí·A. M. Marques·R. G. Dias·A. J. Daley·V. Ahufinger·J. Mompart

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Abstract

We study the single-particle properties of a system formed by ultracold atoms loaded into the manifold of $l=1$ Orbital Angular Momentum (OAM) states of an optical lattice with a diamond chain geometry. Through a series of successive basis rotations, we show that the OAM degree of freedom induces phases in some tunneling amplitudes of the tight-binding model that are equivalent to a net $\pi$ flux through the plaquettes and give rise to a topologically non-trivial band structure and protected edge states. In addition, we demonstrate that quantum interferences between the different tunneling processes involved in the dynamics may lead to Aharanov-Bohm caging in the system. All these analytical results are confirmed by exact diagonalization numerical calculations.

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G. Pelegrí, A. M. Marques, R. G. Dias, A. J. Daley, V. Ahufinger, J. Mompart. 2018-07-19. Topological edge states with ultracold atoms carrying orbital angular momentum in a diamond chain. https://doi.org/10.1103/physreva.99.023612

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