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arXiv · 2108.11183

Pump-induced terahertz anisotropy in bilayer graphene

Angelika Seidl·Roozbeh Anvari·Marc M. Dignam·Peter Richter·Thomas Seyller·Harald Schneider·Manfred Helm·Stephan Winnerl
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Abstract

We investigate the intraband nonlinear dynamics in doped bilayer graphene in the presence of strong, linearly-polarized, in-plane terahertz fields. We perform degenerate pump-probe experiments with 3.4 THz fields on doped bilayer graphene at low temperature (12 K) and find that when the pump is co-polarized with the probe beam, the differential pump-probe signal is almost double that found in the cross-polarized case. We show that the origin of this pump-induced anisotropy is the difference in the average electron effective mass in the probe direction when carriers are displaced in k-space by the pump either parallel or perpendicular to the direction of the probe polarization. We model the system using both a simple semiclassical model and a Boltzmann equation simulation of the electron dynamics with phenomenological scattering and find good qualitative agreement with experimental results.

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Angelika Seidl, Roozbeh Anvari, Marc M. Dignam, Peter Richter, Thomas Seyller, Harald Schneider, Manfred Helm, Stephan Winnerl. 2021-08-25. Pump-induced terahertz anisotropy in bilayer graphene. https://doi.org/10.1103/physrevb.105.085404

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