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arXiv · 1005.0243

Time-dependent density functional theory for quantum transport

Xiao Zheng·GuanHua Chen·Yan Mo·SiuKong Koo·Heng Tian·ChiYung Yam·YiJing Yan
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Abstract

Based on our earlier works [Phys. Rev. B 75, 195127 (2007) & J. Chem. Phys. 128, 234703 (2008)], we propose a formally exact and numerically convenient approach to simulate time-dependent quantum transport from first-principles. The proposed approach combines time-dependent density functional theory with quantum dissipation theory, and results in a useful tool for studying transient dynamics of electronic systems. Within the proposed exact theoretical framework, we construct a number of practical schemes for simulating realistic systems such as nanoscopic electronic devices. Computational cost of each scheme is analyzed, with the expected level of accuracy discussed. As a demonstration, a simulation based on the adiabatic wide-band limit approximation scheme is carried out to characterize the transient current response of a carbon nanotube based electronic device under time-dependent external voltages.

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Xiao Zheng, GuanHua Chen, Yan Mo, SiuKong Koo, Heng Tian, ChiYung Yam, YiJing Yan. 2010-05-03. Time-dependent density functional theory for quantum transport. https://doi.org/10.1063/1.3475566

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