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 π flux through the plaquettes. These effects give rise to a topologically nontrivial band structure and protected edge states which persist everywhere in the parameter space of the model, indicating the absence of a topological transition. By taking advantage of these analytical mappings, we also show that this system constitutes a realization of a square-root topological insulator. 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.

Authors
G. Pelegrí, J. Mompart, V. Ahufinger, A. J. Daley, R. G. Dias, i A. M. Marques
Citation Key
301
COinS Data

Date Published
2019-03-14 08:29
DOI
10.1103/PhysRevA.99.023612
Pagination
023612
Journal
Phys. Rev. A
URL
https://link.aps.org/doi/10.1103/PhysRevA.99.023612
Volume
99
Year of Publication
2019