2015/02/28 by Mekena Metcalf, Gia-Wei Chern, Massimiliano Di Ventra +1
Physics and Astronomy · #Cold Atom Physics and Bose-Einstein Condensates #Lattice (music) #Mixing (physics) #Optical lattice #Quantum many-body systems #Square (algebra) #Square lattice #Topological Materials and Phenomena #Ultracold atom #cond-mat.mes-hall #cond-mat.quant-gas #quant-ph
paper · pdf · doi:10.1088/0953-4075/49/7/075301
published as J. Phys. B: At. Mol. Opt. Phys. 49, 075301 (2016) · 9 pages, 6 figures
arxiv created 2016/01/05 · openalex publication_date 2016/03/17 · arxiv updated 2016/05/02 · openalex created_date 2016/06/24 · openalex updated_date 2026/08/05
The geometry of optical lattices can be engineered, allowing the study of atomic transport along paths arranged in patterns that are otherwise difficult to probe in the solid state. A question feasible to atomic systems is related to the speed of matter-wave propagation as a function of the lattice geometry. To address this issue, we investigated, theoretically, the quantum transport of noninteracting and weakly-interacting ultracold fermionic atoms in several 2D optical lattice geometries. We find that the triangular lattice has a higher propagation velocity compared to the square lattice, and the cross-linked square lattice has an even faster propagation velocity. The increase results from the mixing of the momentum states which leads to different group velocities in quantum systems. Standard band theory provides an explanation and allows for a systematic way to search and design systems with controllable matter-wave propagation. Moreover, the presence of a flat band such as in a two-leg ladder geometry leads to a dynamical density discontinuity due to its localized atoms. Possible realizations of those dynamical phenomena are discussed.