Cold spots in quantum systems far from equilibrium: Local entropies and temperatures near absolute zero

Abhay Shastry and Charles A. Stafford
Phys. Rev. B 92, 245417 – Published 11 December 2015

Abstract

We consider a question motivated by the third law of thermodynamics: Can there be a local temperature arbitrarily close to absolute zero in a nonequilibrium quantum system? We consider nanoscale quantum conductors with the source reservoir held at finite temperature and the drain held at or near absolute zero, a problem outside the scope of linear response theory. We obtain local temperatures close to absolute zero when electrons originating from the finite temperature reservoir undergo destructive quantum interference. The local temperature is computed by numerically solving a nonlinear system of equations describing equilibration of a scanning thermoelectric probe with the system, and we obtain excellent agreement with analytic results derived using the Sommerfeld expansion. A local entropy for a nonequilibrium quantum system is introduced and used as a metric quantifying the departure from local equilibrium. It is shown that the local entropy of the system tends to zero when the probe temperature tends to zero, consistent with the third law of thermodynamics.

  • Figure
  • Figure
  • Figure
  • Figure
  • Received 13 August 2015
  • Revised 14 November 2015

DOI:https://doi.org/10.1103/PhysRevB.92.245417

©2015 American Physical Society

Authors & Affiliations

Abhay Shastry* and Charles A. Stafford

  • Department of Physics, University of Arizona, 1118 East Fourth Street, Tucson, Arizona 85721, USA

  • *Corresponding author: abhayshastry@email.arizona.edu

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 92, Iss. 24 — 15 December 2015

Reuse & Permissions
Access Options
CHORUS

Article Available via CHORUS

Download Accepted Manuscript
Author publication services for translation and copyediting assistance advertisement

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×