Effect of asymmetry on nonlinear optical response in graphene
1 Department of Communication Science and Engineering, Fudan University - Shanghai 200433 China
2 School of Physics, University of Wollongong - New South Wales 2522, Australia
Received: 20 March 2014
Accepted: 17 July 2014
We show that a slight asymmetry in the wave function of graphene can result in a significant enhancement of the nonlinear effect on the optical response. The third-order nonlinear current due to asymmetry modification of the wave function increases with kFa, where kF is the Fermi eigenvector and a is the lattice constant. The effect of asymmetry can significantly enhance the third-order current at low temperature and at large Fermi energies. For kFa around 1, the nonlinear current increases by around 40% at low temperatures.
PACS: 73.50.Mx – High-frequency effects; plasma effects / 78.66.-w – Optical properties of specific thin films / 81.05.uf – Graphite
© EPLA, 2014