Electron-phonon coupling in copper intercalated Bi$_{2}$Se$_{3}$

TL;DR

This study investigates how electron-phonon interactions affect charge and heat transport in copper-intercalated Bi$_2$Se$_3$, revealing a temperature-dependent crossover in heat flux and emphasizing the role of transverse acoustic phonons.

Contribution

It provides new insights into electron-phonon coupling mechanisms in topological insulators through combined transport and noise measurements.

Findings

Heat flux transitions from T^2 to T^4 with temperature.

Electron-phonon coupling involves transverse acoustic phonons.

Quantum corrections influence conductivity.

Abstract

We report charge and heat transport studies in copper-intercalated topological insulator Bi$_2$Se$_3$ hybrid devices. Measured conductivity shows impact of quantum corrections, electron-electron and electron-phonon interactions. Our shot noise measurements reveal that heat flux displays a crossover between $T^2$ and $T^4$ with the increase of temperature. The results can be explained by a model of inelastic electron scattering on disorder, increasing the role of transverse acoustic phonons in the electron-phonon coupling process.