• 文献标题:   Supercollision cooling effects on the hot photoluminescence emission of graphene
  • 文献类型:   Article
  • 作  者:   ALENCAR TV, MALARD LM, DE PAULA AM
  • 作者关键词:   electron dynamic, hot photoluminescence, graphene, defect, electronacoustic phonon supercollision
  • 出版物名称:   NANOTECHNOLOGY
  • ISSN:   0957-4484 EI 1361-6528
  • 通讯作者地址:   Univ Fed Minas Gerais
  • 被引频次:   3
  • DOI:   10.1088/0957-4484/27/44/445710
  • 出版年:   2016

▎ 摘  要

We report on hot photoluminescence measurements that show the effects of acoustic phonon supercollision processes in the intensity of graphene light emission. We use a simple optical method to induce defects on single layer graphene in a controlled manner to study in detail the light emission dependence on the sample defect density. It is now well accepted that the graphene photoluminescence is due to black-body thermal emission from the quasi-equilibrium electrons at a temperature well above the lattice temperature. Our results show that as the sample defect density is increased the electrons relax energy more efficiently via acoustic phonon supercollision processes leading to lower electron temperatures and thus lower emission intensities. The calculated intensity decrease due to supercollision energy relaxation agrees well with the experimental data.