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

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 might be explained by a model of inelastic electron scattering on disorder, increasing the role of transverse acoustic phonons in the electron–phonon coupling process.