• 文献标题:   Emergence of Photoswitchable States in a Graphene-Azobenzene-Au Platform
  • 文献类型:   Article
  • 作  者:   MARGAPOTI E, STROBEL P, ASMAR MM, SEIFERT M, LI J, SACHSENHAUSER M, CEYLAN O, PALMA CA, BARTH JV, GARRIDO JA, CATTANISCHOLZ A, ULLOA SE, FINLEY JJ
  • 作者关键词:   photochromatic molecule, graphene, atomic microscopy, doping
  • 出版物名称:   NANO LETTERS
  • ISSN:   1530-6984 EI 1530-6992
  • 通讯作者地址:   Tech Univ Munich
  • 被引频次:   23
  • DOI:   10.1021/nl503681z
  • 出版年:   2014

▎ 摘  要

The perfect transmission of charge carriers through potential barriers in graphene (Klein tunneling) is a direct consequence of the Dirac equation that governs the low-energy carrier dynamics. As a result, localized states do not exist in unpatterned graphene, but quasibound states can occur for potentials with closed integrable dynamics. Here, we report the observation of resonance states in photoswitchable self-assembled molecular(SAM)-graphene hybrid. Conductive AFM measurements performed at room temperature reveal strong current resonances, the strength of which can be reversibly gated on- and off- by optically switching the molecular conformation of the mSAM. Comparisons of the voltage separation between current resonances (similar to 70-120 mV) with solutions of the Dirac equation indicate that the radius of the gating potential is similar to 7 +/- 2 nm with a strength =0.5 eV. Our results and methods might provide a route toward optically programmable carrier dynamics and transport in graphene nanomaterials.