• 文献标题:   Single-parameter pumping in graphene
  • 文献类型:   Article
  • 作  者:   SANJOSE P, PRADA E, KOHLER S, SCHOMERUS H
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   1098-0121
  • 通讯作者地址:   Inst Estruct Mat IEM CSIC
  • 被引频次:   32
  • DOI:   10.1103/PhysRevB.84.155408
  • 出版年:   2011

▎ 摘  要

We propose a quantum pump mechanism based on the particular properties of graphene, namely chirality and bipolarity. The underlying physics is the excitation of evanescent modes entering a potential barrier from one lead, while those from the other lead do not reach the driving region. This induces a large nonequilibrium current with electrons stemming from a broad range of energies, in contrast to the narrow resonances that govern the corresponding effect in semiconductor heterostructures. Moreover, the pump mechanism in graphene turns out to be robust, with a simple parameter dependence, which is beneficial for applications. Numerical results from a Floquet scattering formalism are complemented with analytical solutions for small to moderate driving.