Artificial graphene with tunable interactions
Abstract
We create an artificial graphene system with tunable interactions and study the crossover from metallic to Mott insulating regimes, both in isolated and coupled two-dimensional honeycomb layers. The artificial graphene consists of a two-component spin mixture of an ultracold atomic Fermi gas loaded into a hexagonal optical lattice. For strong repulsive interactions we observe a suppression of double occupancy and measure a gapped excitation spectrum. We present a quantitative comparison between our measurements and theory, making use of a novel numerical method to obtain Wannier functions for complex lattice structures. Extending our studies to time-resolved measurements, we investigate the equilibration of the double occupancy as a function of lattice loading time.
Keywords
Cite
@article{arxiv.1308.4401,
title = {Artificial graphene with tunable interactions},
author = {Thomas Uehlinger and Gregor Jotzu and Michael Messer and Daniel Greif and Walter Hofstetter and Ulf Bissbort and Tilman Esslinger},
journal= {arXiv preprint arXiv:1308.4401},
year = {2013}
}
Comments
11 pages, 10 figures