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arXiv · 2212.04177

An ab initio supercell approach for high-harmonic generation in liquids

Zahra Nourbakhsh·Ofer Neufeld·Nicolas Tancogne-Dejean·Angel Rubio
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Abstract

Many important ultrafast phenomena take place in the liquid phase. However, there is no practical theory to predict how liquids respond to intense light. Here, we propose an $ab~initio$ accurate method to study the non-perturbative interaction of intense pulses with a liquid target to investigate its high-harmonic emission. We consider the case of liquid water, but the method can be applied to any other liquid or amorphous system. The liquid water structure is reproduced using Car-Parrinello molecular dynamics simulations in a periodic supercell. Then, we employ real-time time-dependent density functional theory to evaluate the light-liquid interaction. We outline the practical numerical conditions to obtain a converged response. Also, we discuss the impact of nuclei ultrafast dynamics on the non-linear response of system. In addition, by considering two different ordered structures of ice, we show how harmonic emission responds to the loss of long-range order in liquid water.

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Zahra Nourbakhsh, Ofer Neufeld, Nicolas Tancogne-Dejean, Angel Rubio. 2022-12-08. An ab initio supercell approach for high-harmonic generation in liquids. https://arxiv.org/abs/2212.04177

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