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arXiv · 1809.01408

Ab initio simulation of attosecond transient absorption spectroscopy in two-dimensional materials

Shunsuke A. Sato·Hannes Hübener·Umberto De Giovannini·Angel Rubio
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Abstract

We extend the first-principles analysis of attosecond transient absorption spectroscopy to two-dimensional materials. As an example of two-dimensional materials, we apply the analysis to monolayer hexagonal boron nitride (h-BN) and compute its transient optical properties under intense few-cycle infrared laser pulses. Nonadiabatic features are observed in the computed transient absorption spectra. To elucidate the microscopic origin of these features, we analyze the electronic structure of h-BN with density functional theory and investigate the dynamics of specific energy bands with a simple two-band model. Finally, we find that laser-induced intraband transitions play a significant role in the transient absorption even for the two-dimensional material and that the nonadiabatic features are induced by the dynamical Franz-Keldysh effect with an anomalous band dispersion.

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Shunsuke A. Sato, Hannes Hübener, Umberto De Giovannini, Angel Rubio. 2018-09-05. Ab initio simulation of attosecond transient absorption spectroscopy in two-dimensional materials. https://doi.org/10.3390/app8101777

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