Energy redistribution between quasiparticles in mesoscopic silver wires

TL;DR

This study measures energy distribution functions in silver wires to understand quasiparticle energy exchange, revealing results consistent with diffusive conductor theory and suggesting additional mechanisms like two-level system coupling.

Contribution

First measurement of quasiparticle energy redistribution in silver wires, demonstrating compatibility with diffusive conductor theory and indicating possible additional mechanisms.

Findings

Energy exchange rate inferred from distribution functions.

Silver wires align with diffusive conductor theory.

Potential coupling to two-level systems suggested.

Abstract

We have measured with a tunnel probe the energy distribution function of quasiparticles in silver diffusive wires connected to two large pads (``reservoirs''), between which a bias voltage was applied. From the dependence in energy and bias voltage of the distribution function we have inferred the energy exchange rate between quasiparticles. In contrast with previously obtained results on copper and gold wires, these data on silver wires can be well interpreted with the theory of diffusive conductors either solely, or associated with another mechanism, possibly the coupling to two-level systems.