title: Anomalous photon-assisted tunneling in  graphene.
abstract: We investigated the transmission of Dirac electrons through a potential barrier in the presence of circularly polarized light. An anomalous photon-assisted enhanced transmission is predicted and explained. It is demonstrated that the perfect transmission for nearly head-on collision in infinite graphene is suppressed in gapped dressed states of electrons, which is further accompanied by a shift of peaks as a function of the incident angle away from head-on collision. In addition, the perfect transmission is partially suppressed by a photon-induced gap in illuminated graphene. After the effect of rough edges of the potential barrier or impurity scattering is included, the perfect transmission with no potential barrier becomes completely suppressed and the energy range for the photon-assisted transmission is reduced at the same time.
authors.affiliation: Department of Physics and Astronomy, Hunter College, City University of New York, 695 Park Avenue, New York, NY 10065, USA.
authors.forename: Andrii
authors.initials: A
authors.lastname: Iurov
authors.forename: Godfrey
authors.initials: G
authors.lastname: Gumbs
authors.forename: Oleksiy
authors.initials: O
authors.lastname: Roslyak
authors.forename: Danhong
authors.initials: D
authors.lastname: Huang