Abstract
We calculate the thermal conductance of diffusive Andreev interferometers, which are hybrid loops with one superconducting arm and one normal-metal arm. The presence of the superconductor suppresses ; however, unlike a conventional superconductor, does not vanish as the temperature , but saturates at a finite value that depends on the resistance of the normal-superconducting interfaces, and their distance from the path of the temperature gradient. The reduction of is determined primarily by the suppression of the density of states in the proximity-coupled normal metal along the path of the temperature gradient. is also a strongly nonlinear function of the thermal current, as found in recent experiments.
- Received 14 April 2004
DOI:https://doi.org/10.1103/PhysRevLett.94.147002
©2005 American Physical Society