• 文献标题:   Sublattice Interference as the Origin of sigma Band Kinks in Graphene
  • 文献类型:   Article
  • 作  者:   JUNG SW, SHIN WJ, KIM J, MORESCHINI L, YEOM HW, ROTENBERG E, BOSTWICK A, KIM KS
  • 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:   Inst for Basic Sci Korea
  • 被引频次:   8
  • DOI:   10.1103/PhysRevLett.116.186802
  • 出版年:   2016

▎ 摘  要

Kinks near the Fermi level observed in angle-resolved photoemission spectroscopy (ARPES) have been widely accepted to represent electronic coupling to collective excitations, but kinks at higher energies have eluded a unified description. We identify the mechanism leading to such kink features by means of ARPES and tight-binding band calculations on sigma bands of graphene, where anomalous kinks at energies as high as similar to 4 eV were reported recently [Phys. Rev. Lett. 111, 216806 (2013)]. We found that two s bands show a strong intensity modulation with abruptly vanishing intensity near the kink features, which is due to sublattice interference. The interference induced local singularity in the matrix element is a critical factor that gives rise to apparent kink features, as confirmed by our spectral simulations without involving any coupling to collective excitations.