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arXiv · 1702.08163

Momentum-resolved TDDFT algorithm in atomic basis for real time tracking of electronic excitation

Chao Lian·Shi-Qi Hu·Meng-Xue Guan·Sheng Meng
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Abstract

Ultrafast electronic dynamics in solids lies at the core of modern condensed matter and materials physics. To build up a practical ab initio method for studying solids under photoexcitation, we develop a momentum-resolved real-time time dependent density functional theory (rt-TDDFT)algorithm using numerical atomic basis, together with the implementation of both the length and vector gauge of the electromagnetic field. When applied to simulate elementary excitations in two-dimensional materials such as graphene, different excitation modes, only distinguishable in momentum space, are observed. The momentum-resolved rt-TDDFT is important and computationally efficient for the study of ultrafast dynamics in extended systems.

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Chao Lian, Shi-Qi Hu, Meng-Xue Guan, Sheng Meng. 2018-10-15. Momentum-resolved TDDFT algorithm in atomic basis for real time tracking of electronic excitation. https://doi.org/10.1063/1.5036543

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