Calorimetric tunneling study of heat generation in metal-vacuum-metal tunnel junction

TL;DR

This study introduces a novel calorimetric tunneling technique to precisely measure heat generation in metal-vacuum-metal junctions, revealing how heat redistribution depends on bias voltage and tunnel current direction, linked to non-equilibrium quasiparticles.

Contribution

The paper presents a new calorimetric tunneling method for exact heat measurement in tunnel junctions, advancing experimental capabilities in nanoscale heat transfer analysis.

Findings

Heat redistribution depends on bias voltage and current direction.

Total heat equals Joule heat, confirming energy conservation.

Generated heat relates to non-equilibrium quasiparticles.

Abstract

We have proposed novel calorimetric tunneling (CT) experiment allowing exact determination of heat generation (or heat sinking) in individual tunnel junction (TJ) electrodes which opens new possibilities in the field of design and development of experimental techniques for science and technology. Using such experiment we have studied the process of heat generation in normal-metal electrodes of the vacuum-barrier tunnel junction (VBTJ). The results show there exists dependence of the mutual redistribution of the heat on applied bias voltage and the direction of tunnel current, although the total heat generated in tunnel process is equal to Joule heat, as expected. Moreover, presented study indicates generated heat represents the energy of non-equilibrium quasiparticles coming from inelastic electron processes accompanying the process of elastic tunneling.