We numerically investigate the heat conduction in a random-exchange Ising spin chain by using the quantum master equation. The chain is subject to a uniform transverse field h, while the exchange couplings {Qn} between the nearest neighbor spins are random; the largest size we simulate is up to 10. This model is integrable; i.e., the nearest neighbor level spacing distribution is Poissonian. However, we find clear evidence of nonballistic transport. In the small coupling regime (Qn≪h), an energy and/or temperature gradient in the bulk of the system is observed and the energy current appears to be proportional to the inverse of the system size. Moreover, we find that in the low and high temperature regimes, the thermal conductivity κ and the specific heat Cv have the same dependence on temperature. The large coupling case (Qn∼h) is also discussed.

Nonballistic heat conduction in an integrable random-exchange Ising chain studied with quantum master equations

CASATI, GIULIO;
2008-01-01

Abstract

We numerically investigate the heat conduction in a random-exchange Ising spin chain by using the quantum master equation. The chain is subject to a uniform transverse field h, while the exchange couplings {Qn} between the nearest neighbor spins are random; the largest size we simulate is up to 10. This model is integrable; i.e., the nearest neighbor level spacing distribution is Poissonian. However, we find clear evidence of nonballistic transport. In the small coupling regime (Qn≪h), an energy and/or temperature gradient in the bulk of the system is observed and the energy current appears to be proportional to the inverse of the system size. Moreover, we find that in the low and high temperature regimes, the thermal conductivity κ and the specific heat Cv have the same dependence on temperature. The large coupling case (Qn∼h) is also discussed.
2008
http://journals.aps.org/prb/abstract/10.1103/PhysRevB.77.172411
Yonghong, Yan; CHANG QIN, Wu; Casati, Giulio; T., Prosen; Baowen, Li; Y., Yan; C., Wu; T., Prosen; B., Li
File in questo prodotto:
File Dimensione Formato  
PhysRevB.77.172411.pdf

accesso aperto

Descrizione: PDF editoriale
Tipologia: Altro materiale allegato
Licenza: Creative commons
Dimensione 648.98 kB
Formato Adobe PDF
648.98 kB Adobe PDF Visualizza/Apri

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/11383/14733
Citazioni
  • ???jsp.display-item.citation.pmc??? ND
  • Scopus 18
  • ???jsp.display-item.citation.isi??? 19
social impact