Temperature induced crossover in the collision-dominated Dirac semimetal Cd₃As₂

The 3D topological Dirac semimetal Cd₃As₂ was studied in a wide range of temperatures and excitation energies using Raman spectroscopy. The temperature evolution of the phononic and the quasielastic electronic scattering is discussed in terms of a collision-dominated regime with pronounced electronic energy density fluctuations. A crossover is observed in the intensity of the signals attributed to a collision-dominated phonon regime.