First Principles Simulation of Time-dependent Quantum Transport: Dynamic
Admittance, Equivalent Circuit and Current Spectrum
Xiao Zheng3, ChiYung Yam1, GuanHua Chen1*, Yan Mo2, and YiJing Yan2*
1
2
Department of Chemistry, The University of Hong Kong, Hong Kong
Department of Chemistry, The Hong Kong University of Science and Technology, Hong Kong
3
Department of Chemistry, Duke University, USA
Abstract
We carry out first-principles calculation on the transient electrical response of carbon
nanotube-based conductors under time-dependent bias voltages. The dynamic admittance as well as
transient charge and potential distributions are analyzed. We find that in the linear regime, the
dynamic current response of naonotube-based conductors can be mapped onto an equivalent
classical electric circuit. The switching time of these end-on carbon nanotube devices is as short as
a few femtoseconds. This result is then generalized to other two-terminal molecular electronic
devices. We also explore the nonlinear regime by looking into the response current spectrum, which
resolves the characteristic energetic features of nanoscopic devices.
Contact Info:
Xiao Zheng [presenter’s name]
Professor [position]
Hefei National Laboratory for Physical Sciences at the Microscale [Institution]
Address: Hefei National Laboratory for Physical Sciences at the Microscale,
University of Science and Technology of China, Hefei, 230026, China
Email: xz58@ustc.edu.cn
Tel: 919xxxxxx [optional]