• 文献标题:   Floquet analysis of pulsed Dirac systems: a way to simulate rippled graphene
  • 文献类型:   Article
  • 作  者:   MISHRA T, SARKAR TG, BANDYOPADHYAY JN
  • 作者关键词:  
  • 出版物名称:   EUROPEAN PHYSICAL JOURNAL B
  • ISSN:   1434-6028 EI 1434-6036
  • 通讯作者地址:   Birla Inst Technol Sci
  • 被引频次:   6
  • DOI:   10.1140/epjb/e2015-60356-2
  • 出版年:   2015

▎ 摘  要

The low energy continuum limit of graphene is effectively known to be modeled using the Dirac equation in (2 + 1) dimensions. We consider the possibility of using a modulated high frequency periodic driving of a two-dimensional system (optical lattice) to simulate properties of rippled graphene. We suggest that the Dirac Hamiltonian in a curved background space can also be effectively simulated by a suitable driving scheme in an optical lattice. The time dependent system yields, in the approximate limit of high frequency pulsing, an effective time independent Hamiltonian that governs the time evolution, except for an initial and a final kick. We use a specific form of 4-phase pulsed forcing with suitably tuned choice of modulating operators to mimic the effects of curvature. The extent of curvature is found to be directly related to omega(-1) the time period of the driving field at the leading order. We apply the method to engineer the effects of curved background space. We find that the imprint of curvilinear geometry modifies the electronic properties, such as LDOS, significantly. We suggest that this method shall be useful in studying the response of various properties of such systems to non-trivial geometry without requiring any actual physical deformations.