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arXiv · 1509.01527

Sound waves induce Volkov-like states, band structure and collimation effect in graphene

M. Oliva-Leyva·G. G. Naumis
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Abstract

We find exact states of graphene quasiparticles under a time-dependent deformation (sound wave), whose propagation velocity is smaller than the Fermi velocity. To solve the corresponding effective Dirac equation, we adapt the Volkov-like solutions for relativistic fermions in a medium under a plane electromagnetic wave. The corresponding electron-deformation quasiparticle spectrum is determined by the solutions of a Mathieu equation resulting in band tongues warped in the surface of the Dirac cones. This leads to a collimation effect of electron conduction due to strain waves.

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M. Oliva-Leyva, G. G. Naumis. 2017-02-08. Sound waves induce Volkov-like states, band structure and collimation effect in graphene. https://doi.org/10.1088/0953-8984%2F28%2F2%2F025301

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