dc.contributor.author | SANVITO, STEFANO | |
dc.date.accessioned | 2014-02-03T12:52:52Z | |
dc.date.available | 2014-02-03T12:52:52Z | |
dc.date.issued | 2009 | |
dc.date.submitted | 2009 | en |
dc.identifier.citation | William Lee, Nicola Jean, Stefano Sanvito, Exploring the limits of the self consistent Born approximation for inelastic electronic transport, Physical Review B, 79, 2009, 085120 | en |
dc.identifier.other | Y | |
dc.description | PUBLISHED | en |
dc.description.abstract | The non equilibrium Green function formalism is today the st
andard computational method for
describing elastic transport in molecular devices. This ca
n be extended to include inelastic scattering
by the so called self-consistent Born approximation (SCBA)
, where the interaction of the electrons
with the vibrations of the molecule is assumed to be weak and i
t is treated perturbatively. The
validity of such an assumption and therefore of the SCBA is di
fficult to establish with certainty.
In this work we explore the limitations of the SCBA by using a s
imple tight-binding model with
the electron-phonon coupling strength
?
chosen as a free parameter. As model devices we consider
Au mono-atomic chains and a H
2
molecule sandwiched between Pt electrodes. In both cases ou
r
self-consistent calculations demonstrate a breakdown of t
he SCBA for large
?
and we identify a
weak and strong coupling regime. For weak coupling our SCBA r
esults compare closely with those
obtained with exact scattering theory. However in the stron
g coupling regime large deviations are
found. In particular we demonstrate that there is a critical
coupling strength, characteristic of the
materials system, beyond which multiple self-consistent s
olutions can be found depending on the
initial conditions in the simulation. We attribute these fe
atures to the breakdown of the perturbative
expansion leading to the SCBA. | en |
dc.description.sponsorship | IRCSET | en |
dc.format.extent | 085120 | en |
dc.language.iso | en | en |
dc.relation.ispartofseries | Physical Review B; | |
dc.relation.ispartofseries | 79; | |
dc.rights | Y | en |
dc.subject | Physics | en |
dc.title | Exploring the limits of the self consistent Born approximation for inelastic electronic transport | en |
dc.type | Journal Article | en |
dc.type.supercollection | scholarly_publications | en |
dc.type.supercollection | refereed_publications | en |
dc.identifier.peoplefinderurl | http://people.tcd.ie/sanvitos | |
dc.identifier.rssinternalid | 50855 | |
dc.rights.ecaccessrights | OpenAccess | |
dc.identifier.rssuri | http://arxiv.org/pdf/0804.3389v1.pdf | en |
dc.identifier.uri | http://hdl.handle.net/2262/67973 | |