Empirical tight binding parameters for GaAs and MgO with explicit basis through DFT mapping

Yaohua Tan, Birck Nanotechnology Center, Purdue University
Michael Povolotskyi, Birck Nanotechnology Center, Purdue University
Tillmann Kubis, Birck Nanotechnology Center, Purdue University
Yu He, Birck Nanotechnology Center, Purdue University
Zhengping Jiang, Birck Nanotechnology Center, Purdue University
Gerhard Klimeck, Network for Computational Nanotechnology, Birck Nanotechnology Center, Purdue University
Timothy B. Boykin, University of Alabama Huntsville

Date of this Version

3-2013

Citation

Tan, Y., Povolotskyi, M., Kubis, T. et al. J Comput Electron (2013) 12: 56.

Abstract

The Empirical Tight Binding (ETB) method is widely used in atomistic device simulations. The reliability of such simulations depends very strongly on the choice of basis sets and the ETB parameters. The traditional way of obtaining the ETB parameters is by fitting to experiment data, or critical theoretical bandedges and symmetries rather than a foundational mapping. A further shortcoming of traditional ETB is the lack of an explicit basis. In this work, a DFT mapping process which constructs TB parameters and explicit basis from DFT calculations is developed. The method is applied to two materials: GaAs and MgO. Compared with the existing TB parameters, the GaAs parameters by DFT mapping show better agreement with the DFT results in bulk band structure calculations and lead to different indirect valleys when applied to nanowire calculations. The MgO TB parameters and TB basis functions are also obtained through the DFT mapping process.

Discipline(s)

Nanoscience and Nanotechnology

 

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