Investigation of the Electron–Phonon Coupling in Dirac Semimetal PdTe2 via Temperature‐Dependent Raman Spectroscopy

Layered Palladium ditelluride (PdTe2) is an interesting noble‐transition‐metal dichalcogenide with high electrical and thermal conductivity, exhibiting superconductivity and a type‐II Dirac semimetallic phase due to the increased electron–phonon (e–ph) coupling. Herein, the e–ph coupling constant λ of E g (in‐plane) and A 1g (out‐of‐plane) modes in the exfoliated PdTe2 nanoflakes via temperature‐dependent Raman spectroscopy within the temperature range from 80 to 580 K is determined. Both E g mode with a Gaussian line shape and A 1g mode with a Breit–Wigner–Fano line shape show nonlinear frequency redshift and linewidth broadening with temperature. The extracted e–ph coupling constants are λ E g = 1.54 and λ A 1 g = 0.55, respectively. The Raman results confirm that PdTe2 is a phonon‐mediated Bardeen–Cooper–Schrieffer superconductor. This study investigates the electron–phonon coupling and the phonon anharmonicity in Raman‐active modes (E g and A 1g) in the exfoliated PdTe2 nanoflakes based on temperature‐dependent Raman scattering. Both E g mode with a Gaussian lineshape and A 1g mode with a Fano line shape show nonlinear frequency redshift, linewidth broadening with temperature, revealing the different electron–phonon coupling constants.