Linear and nonlinear optical probe of the ferroelectric-like phase transition in a polar metal, LiOsO3
Document Type
Article
Publication Date
9-17-2018
Abstract
LiOsO3 is one of the first materials identified in the recent literature as a "polar metal," a class of materials that are simultaneously noncentrosymmetric and metallic. In this work, the linear and nonlinear optical susceptibility of LiOsO3 is studied by means of ellipsometry and optical second harmonic generation (SHG). Strong optical birefringence is observed using spectroscopic ellipsometry. The nonlinear optical susceptibility extracted from SHG polarimetry reveals that the tensor components are of the same magnitude as in the isostructural insulator LiNbO3, except the component along the polar axis d33 is suppressed by an order of magnitude. Temperature-dependent SHG measurements in combination with Raman spectroscopy indicate a continuous order-disorder type polar phase transition at 140 K. Linear and nonlinear optical microscopy measurements reveal 109°/71° ferroelastic domain walls, like in other trigonal ferroelectrics. No 180° polar domain walls are observed to emerge across the phase transition.
Publication Title
Applied Physics Letters
Volume
113
Issue
12
Digital Object Identifier (DOI)
10.1063/1.5042769
ISSN
00036951
Citation Information
Padmanabhan, Park, Y., Puggioni, D., Yuan, Y., Cao, Y., Gasparov, L., Shi, Y., Chakhalian, J., Rondinelli, J. M., & Gopalan, V. (2018). Linear and nonlinear optical probe of the ferroelectric-like phase transition in a polar metal, LiOsO3. Applied Physics Letters, 113(12), 122906–. https://doi.org/10.1063/1.5042769