• 文献标题:   Generalizing the Fermi velocity of strained graphene from uniform to nonuniform strain
  • 文献类型:   Article
  • 作  者:   OLIVALEYVA M, NAUMIS GG
  • 作者关键词:  
  • 出版物名称:   PHYSICS LETTERS A
  • ISSN:   0375-9601 EI 1873-2429
  • 通讯作者地址:   Univ Nacl Autonoma Mexico
  • 被引频次:   30
  • DOI:   10.1016/j.physleta.2015.05.039
  • 出版年:   2015

▎ 摘  要

The relevance of the strain-induced Dirac point shift to obtain the appropriate anisotropic Fermi velocity of strained graphene is demonstrated. Then a critical revision of the available effective Dirac Hamiltonians is made by studying in detail the limiting case of a uniform strain. An effective Dirac Hamiltonian for nonuniform strain is thus reported, which takes into account all strain-induced effects: changes in the nearest-neighbor hopping parameters, the reciprocal lattice deformation and the true shift of the Dirac point. Pseudomagnetic fields are thus explained by means of position-dependent Dirac cones, whereas complex gauge fields appear as a consequence of a position-dependent Fermi velocity. Also, position-dependent Fermi velocity effects on the spinor wavefunction are considered for interesting cases of deformations such as flexural modes. (C) 2015 Elsevier B.V. All rights reserved.