• 文献标题:   Artificial Graphene with Tunable Interactions
  • 文献类型:   Article
  • 作  者:   UEHLINGER T, JOTZU G, MESSER M, GREIF D, HOFSTETTER W, BISSBORT U, ESSLINGER T
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW LETTERS
  • ISSN:   0031-9007 EI 1079-7114
  • 通讯作者地址:   ETH
  • 被引频次:   94
  • DOI:   10.1103/PhysRevLett.111.185307
  • 出版年:   2013

▎ 摘  要

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.