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arXiv · 2304.02320

Graphene valley polarization as a function of carrier-envelope phase in few-cycle laser pulses and its footprints in harmonic signals

H. K. Avetissian·V. A. Sedrakyan·Kh. V. Sedrakian·G. F. Mkrtchian
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Abstract

We consider coherent dynamics of graphene charged carriers exposed to an intense few-cycle linearly polarized laser pulse. The results, obtained by solving the generalized semiconductor Bloch equations numerically in the Hartree-Fock approximation, taking into account many-body Coulomb interaction, demonstrate strong dependence of the valley polarization on the carrier-envelope phase (CEP), which is interpolated by the simple sinusoidal law. Then we consider harmonic generation in multi-cycle laser field by graphene preliminary exposed to an intense few-cycle laser pulse. We show that the second harmonic's intensity is a robust observable quantity that provides a gauge of CEP for pulse durations up to two optical cycles, corresponding to 40 $\mathrm{fs}$ at the wavelength of 6.2 $\mathrm{\mu m}$.

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H. K. Avetissian, V. A. Sedrakyan, Kh. V. Sedrakian, G. F. Mkrtchian. 2023-04-05. Graphene valley polarization as a function of carrier-envelope phase in few-cycle laser pulses and its footprints in harmonic signals. https://doi.org/10.1103/physrevb.107.205403

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