Matterwave propagation in optical lattices: geometrical and flatband effects
Here we report that 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 propagation of matterwaves as a function of the lattice geometry. To address this issue, we have investigated theoretically the quantum transport of noninteracting and weaklyinteracting 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 crosslinked 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 matterwave propagation. Moreover, the presence of a flat band such as in a twoleg ladder geometry leads to a dynamical density discontinuity due to its localized atoms. Lastly, we discuss possible realizations of those dynamical phenomena.
 Authors:

^{[1]};
^{[2]};
^{[3]};
^{[1]}
 Univ. of California, Merced, CA (United States).School of Natural Sciences
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States). Theoretical Division and Center for Nonlinear Science
 Univ. of California San Diego, La Jolla, CA (United States). Dept. of Physics
 Publication Date:
 Report Number(s):
 LAUR1521107
Journal ID: ISSN 09534075; 13616455 (Electronic)
 Grant/Contract Number:
 AC5206NA25396; FG0205ER46204; LANL/LDRD
 Type:
 Accepted Manuscript
 Journal Name:
 Journal of Physics. B, Atomic, Molecular and Optical Physics
 Additional Journal Information:
 Journal Volume: 49; Journal Issue: 7; Journal ID: ISSN 09534075
 Publisher:
 IOP Publishing
 Research Org:
 Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
 Sponsoring Org:
 USDOE: LDRD; USDOE
 Country of Publication:
 United States
 Language:
 English
 Subject:
 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; optical lattice; atomic transport; nuclear physics
 OSTI Identifier:
 1329569
 Alternate Identifier(s):
 OSTI ID: 1242316
Metcalf, Mekena, Chern, GiaWei, Di Ventra, Massimiliano, and Chien, ChihChun. Matterwave propagation in optical lattices: geometrical and flatband effects. United States: N. p.,
Web. doi:10.1088/09534075/49/7/075301.
Metcalf, Mekena, Chern, GiaWei, Di Ventra, Massimiliano, & Chien, ChihChun. Matterwave propagation in optical lattices: geometrical and flatband effects. United States. doi:10.1088/09534075/49/7/075301.
Metcalf, Mekena, Chern, GiaWei, Di Ventra, Massimiliano, and Chien, ChihChun. 2016.
"Matterwave propagation in optical lattices: geometrical and flatband effects". United States.
doi:10.1088/09534075/49/7/075301. https://www.osti.gov/servlets/purl/1329569.
@article{osti_1329569,
title = {Matterwave propagation in optical lattices: geometrical and flatband effects},
author = {Metcalf, Mekena and Chern, GiaWei and Di Ventra, Massimiliano and Chien, ChihChun},
abstractNote = {Here we report that 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 propagation of matterwaves as a function of the lattice geometry. To address this issue, we have investigated theoretically the quantum transport of noninteracting and weaklyinteracting 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 crosslinked 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 matterwave propagation. Moreover, the presence of a flat band such as in a twoleg ladder geometry leads to a dynamical density discontinuity due to its localized atoms. Lastly, we discuss possible realizations of those dynamical phenomena.},
doi = {10.1088/09534075/49/7/075301},
journal = {Journal of Physics. B, Atomic, Molecular and Optical Physics},
number = 7,
volume = 49,
place = {United States},
year = {2016},
month = {3}
}