Open AccessSize-dependent two-photon absorption in circular graphene quantum dots
Author(s) -
Xiaobo Feng,
Xin Li,
Zhisong Li,
Yingkai Liu
Publication year - 2016
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.24.002877
Subject(s) - graphene , quantum dot , photon , attenuation coefficient , physics , absorption (acoustics) , condensed matter physics , photon energy , dirac equation , molecular electronic transition , materials science , atomic physics , optics , quantum mechanics , excited state
We investigate theoretically the size-dependence of two-photon absorption (TPA) for circular graphene quantum dots (GQDs) on the basis of electronic energy states obtained by solving the Dirac-Weyl equation analytically under infinite-mass boundary condition. The analytical expressions for TPA coefficient are derived with an arbitrary size-distribution and the transition selection rules are obtained. Results reveal that the intraband transitions in conduction band and valence band contribute much more to TPA than interband transitions. The energy spectrum and TPA peaks are tuned by the size of GQDs.