Nonconservative current-driven dynamics: beyond the nanoscale


Autoria(s): Cunningham, Brian; Todorov, Tchavdar N.; Dundas, Daniel
Data(s)

13/11/2015

Resumo

<p>Long metallic nanowires combine crucial factors for nonconservative current-driven atomic motion. These systems have degenerate vibrational frequencies, clustered about a Kohn anomaly in the dispersion relation, that can couple under current to form nonequilibrium modes of motion growing exponentially in time. Such motion is made possible by nonconservative current-induced forces on atoms, and we refer to it generically as the waterwheel effect. Here the connection between the waterwheel effect and the stimulated directional emission of phonons propagating along the electron flow is discussed in an intuitive manner. Nonadiabatic molecular dynamics show that waterwheel modes self-regulate by reducing the current and by populating modes in nearby frequency, leading to a dynamical steady state in which nonconservative forces are counter-balanced by the electronic friction. The waterwheel effect can be described by an appropriate effective nonequilibrium dynamical response matrix. We show that the current-induced parts of this matrix in metallic systems are long-ranged, especially at low bias. This nonlocality is essential for the characterisation of nonconservative atomic dynamics under current beyond the nanoscale.</p>

Identificador

http://pure.qub.ac.uk/portal/en/publications/nonconservative-currentdriven-dynamics-beyond-the-nanoscale(71d67719-2de4-47d0-9761-c648b4d08d8e).html

http://dx.doi.org/10.3762/bjnano.6.219

http://www.scopus.com/inward/record.url?scp=84947922840&partnerID=8YFLogxK

Idioma(s)

eng

Direitos

info:eu-repo/semantics/restrictedAccess

Fonte

Cunningham , B , Todorov , T N & Dundas , D 2015 , ' Nonconservative current-driven dynamics: beyond the nanoscale ' Beilstein Journal of Nanotechnology , vol 6 , no. 1 , pp. 2140-2147 . DOI: 10.3762/bjnano.6.219

Palavras-Chave #Atomic-scale conductors #Current-induced forces #Electronic transport #Failure mechanisms #Nanoelectronic devices #Nanomotors #/dk/atira/pure/subjectarea/asjc/2500 #Materials Science(all) #/dk/atira/pure/subjectarea/asjc/2200/2208 #Electrical and Electronic Engineering #/dk/atira/pure/subjectarea/asjc/3100 #Physics and Astronomy(all)
Tipo

article