Raman phonons in the ferroelectric-like metal LiOsO${}_3$

Abstract

The novel ferroelectric-like structural transition observed in metallic LiOsO${}_3$ [Y. Shi et al., Nat. Mater. 12, 1024 (2013)], has invoked many theoretical and experimental interests. In this work, we have performed polarized and temperature-dependent Raman scattering measurements on high-quality single crystal LiOsO${}_3$ and identified Raman-active modes in both centrosymmetric phase (300 K, R$\bar{3}$c) and non-centrosymmetric phase (10 K, R3c). Only four phonon peaks are observed in the former phase, while there are twelve peaks in the latter phase because of the reduction of crystal symmetry. With the help of careful symmetry analysis and first-principles calculations, we can make a systematic assignment for the observed Raman modes in both phases. The significant changes in line-width and the continuous evolution of Raman frequencies with temperatures were observed for the E${}_g$ modes around the transition temperature, which suggests that the ferroelectric-like structural transition is a continuous order-disorder transition. The result sheds light on the coexistence of ferroelectricity and metallicity in the compound.

References in corpus (3)

• Metallic "Ferroelectricity" in the Pyrochlore Cd2Re2O7
• Dual nature of the ferroelectric and metallic state in LiOsO${}_3$
• Metallic ferroelectricity induced by anisotropic unscreened coulomb interaction in LiOsO3

Cited by in corpus (5)

• Evidence for the weakly coupled electron mechanism in an Anderson-Blount polar metal
• Coexistence of polar distortion and metallicity in PbTi1-xNbxO3
• Polar Metals Taxonomy for Materials Classification and Discovery
• Influences of spin-orbit coupling on Fermi surfaces and Dirac cones in ferroelectric-like polar metals
• Evidence for an extended critical fluctuation region above the polar ordering transition in LiOsO${}_3$