We investigate the time-resolved quantum transport properties of phonons in arbitrary harmonic systems connected to phonon baths at different temperatures. We obtain a closed analytic expression of the time-dependent one-particle reduced density matrix by explicitly solving the equations of motion for the nonequilibrium Green's function. This is achieved through a well-controlled approximation of the frequency-dependent bath self-energy. Our result allows for exploring transient oscillations and relaxation times of local heat currents, and correctly reduces to an earlier known result in the steady-state limit. We apply the formalism to atomic chains, and benchmark the validity of the approximation against full numerical solutions of the bosonic Kadanoff-Baym equations for the Green's function. We find good agreement between the analytic and numerical solutions for weak contacts and baths with a wide energy dispersion. We further analyze relaxation times from low to high temperature gradients.

Tuovinen, R., Säkkinen, N., Karlsson, D., Stefanucci, G., Van Leeuwen, R. (2016). Phononic heat transport in the transient regime: An analytic solution. PHYSICAL REVIEW. B, 93(21) [10.1103/PhysRevB.93.214301].

Phononic heat transport in the transient regime: An analytic solution

STEFANUCCI, GIANLUCA;
2016-01-01

Abstract

We investigate the time-resolved quantum transport properties of phonons in arbitrary harmonic systems connected to phonon baths at different temperatures. We obtain a closed analytic expression of the time-dependent one-particle reduced density matrix by explicitly solving the equations of motion for the nonequilibrium Green's function. This is achieved through a well-controlled approximation of the frequency-dependent bath self-energy. Our result allows for exploring transient oscillations and relaxation times of local heat currents, and correctly reduces to an earlier known result in the steady-state limit. We apply the formalism to atomic chains, and benchmark the validity of the approximation against full numerical solutions of the bosonic Kadanoff-Baym equations for the Green's function. We find good agreement between the analytic and numerical solutions for weak contacts and baths with a wide energy dispersion. We further analyze relaxation times from low to high temperature gradients.
2016
Pubblicato
Rilevanza internazionale
Articolo
Sì, ma tipo non specificato
Settore FIS/03 - FISICA DELLA MATERIA
English
Electronic, Optical and Magnetic Materials; Condensed Matter Physics
http://harvest.aps.org/bagit/articles/10.1103/PhysRevB.93.214301/apsxml
Tuovinen, R., Säkkinen, N., Karlsson, D., Stefanucci, G., Van Leeuwen, R. (2016). Phononic heat transport in the transient regime: An analytic solution. PHYSICAL REVIEW. B, 93(21) [10.1103/PhysRevB.93.214301].
Tuovinen, R; Säkkinen, N; Karlsson, D; Stefanucci, G; Van Leeuwen, R
Articolo su rivista
File in questo prodotto:
File Dimensione Formato  
TDLBphononResubmit.pdf

solo utenti autorizzati

Licenza: Non specificato
Dimensione 3.61 MB
Formato Adobe PDF
3.61 MB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/2108/174011
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 24
  • ???jsp.display-item.citation.isi??? 24
social impact