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arXiv · 0805.2736

Quasienergy spectra of a charged particle in planar honeycomb lattices

Wei Zhang·Ping Zhang·Suqing Duan·Xian-Geng Zhao
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Abstract

The low energy spectrum of a particle in planar honeycomb lattices is conical, which leads to the unusual electronic properties of graphene. In this letter we calculate the quasienergy spectra of a charged particle in honeycomb lattices driven by a strong AC field, which is of fundamental importance for its time-dependent dynamics. We find that depending on the amplitude, direction and frequency of external field, many interesting phenomena may occur, including band collapse, renormalization of velocity of ``light'', gap opening etc.. Under suitable conditions, with increasing the magnitude of the AC field, a series of phase transitions from gapless phases to gapped phases appear alternatively. At the same time, the Dirac points may disappear or change to a line. We suggest possible realization of the system in Honeycomb optical lattices.

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Wei Zhang, Ping Zhang, Suqing Duan, Xian-Geng Zhao. 2008-05-18. Quasienergy spectra of a charged particle in planar honeycomb lattices. https://doi.org/10.1088/1367-2630%2F11%2F6%2F063032

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