Theory of electron Zitterbewegung in graphene probed by femtosecond laser pulses

Abstract

We propose an experiment allowing an observation of Zitterbewegung (ZB, trembling motion) of electrons in graphene in the presence of a magnetic field. In contrast to the existing theoretical work we make no assumptions concerning shape of the electron wave packet. A femtosecond Gaussian laser pulse excites electrons from the valence $n=\ensuremath{-}1$ Landau level into three other levels, creating an oscillating electron wave packet with interband and intraband frequencies. Oscillations of an average position of the packet are directly related to the induced dipole moment and oscillations of the average packet's acceleration determine emitted electric field. Both quantities can be measured experimentally. A broadening of Landau levels is included to make the description of ZB as realistic as possible. Criteria of realization of a ZB experiment are discussed.