Mera, H, Bokes, P and Godby, R W (2005) Asymptotic self-consistency in quantum transport calculations. Physical Review B. 085311. -. ISSN 1550-235X
Ab initio simulations of quantum transport commonly focus on a central region which is considered to be connected to infinite leads through which the current flows. The electronic structure of these distant leads is normally obtained from an equilibrium calculation, ignoring the self-consistent response of the leads to the current. We examine the consequences of this, and show that the electrostatic potential Delta phi is effectively being approximated by the difference between electrochemical potentials Delta mu, and that this approximation is incompatible with asymptotic charge neutrality. In a test calculation for a simple metal-vacuum-metal junction, we find significant errors in the nonequilibrium properties calculated with this approximation, in the limit of small vacuum gaps. We provide a scheme by which these errors may be corrected.
|Copyright, Publisher and Additional Information:||© 2005 American Physical Society. This is an author produced version of a paper published in Physical Review B. Uploaded in accordance with the publisher's self archiving policy.|
|Institution:||The University of York|
|Academic Units:||The University of York > Physics (York)|
|Depositing User:||Physics Import|
|Date Deposited:||19 Aug 2008 08:57|
|Last Modified:||03 Apr 2016 00:03|