Phonon softening and electron-phonon coupling in the topological nodal-line semimetal ZrGeSe
Publication Name
Physical Review Materials
Abstract
ZrGeSe is one of the most well-known topological nodal-line semimetals, which possesses linearly dispersive electronic bands near the Fermi surface. However, the lattice-dynamics study and its interaction with the electronic system have not been investigated. We employed the inelastic neutron-scattering method to study the lattice dynamics of ZrGeSe single crystals. The measured acoustic phonon dispersions were compared with lattice-dynamics calculations, with an overall good agreement with theory; however, both the longitudinal and the transverse acoustic phonon dispersions along the (q00) directions demonstrate significant softening, unexpectedly in contrast with the theoretical predictions. Complementary ab initio molecular dynamics simulations indicate an anomalous temperature dependency in the vibrational spectroscopy. We show that strong electron-phonon coupling exists along the Γ-M-X directions and argue that the phonon softening is induced by such electron-phonon coupling.
Open Access Status
This publication is not available as open access
Volume
8
Issue
3
Article Number
034201
Funding Number
CE170100039
Funding Sponsor
Australian Government