Ultrafast optical currents in gapped graphene.

J Phys Condens Matter

Center for Nano-Optics (CeNO) and Department of Physics and Astronomy, Georgia State University, Atlanta, GA 30303, United States of America.

Published: February 2020

We theoretically study the interaction of ultrashort optical pulses with gapped graphene. Such a strong pulse results in a finite conduction band population and a corresponding electric current, both during and after the pulse. Since gapped graphene has broken inversion symmetry, it has an axial symmetry about the y -axis but not about the x-axis. We show that, in this case, if the linear pulse is polarized along the x-axis, the rectified electric current is generated in the y  direction. At the same time, the conduction band population distribution in the reciprocal space is symmetric about the x-axis. Thus, the rectified current in gapped graphene has an inter-band origin, while the intra-band contribution to the rectified current is zero.

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http://dx.doi.org/10.1088/1361-648X/ab4fc7DOI Listing

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