A first-principles LCAO formalism for the linear response quantum conductance of nanostructures
Young-Gui Yoon,1,2 Hyoung Joon Choi,1,3 Mario S. Mazzoni,1 and Steven G. Louie1
1Department of Physics, University of California at Berkeley, Berkeley, CA 94720 U.S.A. and Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 U.S.A.
2Department of Physics, Chung-Ang University, Seoul 156-756, Korea
3Korea Institute for Advanced Study, Seoul 130-722, Korea
We present a first-principles LCAO formalism for calculating quantum conductance of nanostructures. It is based on the Landauer-Buttiker formalism for the conductance of multi-terminal configurations of mesoscopic systems. We calculate self-consistent Hamiltonian matrix elements using an LCAO basis set, and obtain the quantum conductance from the transmission coefficients in the linear-response regime. As examples, we analyze a boron-substituted carbon nanotube and a crossed carbon nanotube junction.