Year: 2024
Type: article
Abstract: Polarimetric infrared (IR) detection bolsters IR thermography by leveraging the polarization of light. Optical anisotropy, i.e., birefringence and dichroism, can be leveraged to achieve polarimetric detection. Recently, giant optical anisotropy is discovered in quasi‐1D narrow‐bandgap hexagonal perovskite sulfides, A1+xTiS3, specifically BaTiS3 and Sr9/8TiS3. In these materials, the critical role of atomic‐scale structure modulations in the unconventional electrical, optical, and thermal properties raises the broader question of the nature of other materials that belong to this family. To address this issue, for the first time, high‐quality single crystals of a largely unexplored member of the A1+xTiX3 (X = S, Se) family, BaTiSe3 are synthesized. Single‐crystal X‐ray diffraction determined the room‐temperature structure with the P31c space group, which is a superstructure of the earlier reported P63/mmc structure. The crystal structure of BaTiSe3 features antiparallel c‐axis displacements similar to but of lower symmetry than BaTiS3, verified by the polarization dependent Raman spectroscopy. Fourier transform infrared (FTIR) spectroscopy is used to characterize the optical anisotropy of BaTiSe3, whose refractive index along the ordinary (E ⊥ c) and extraordinary (E ‖ c) optical axes is quantitatively determined by combining ellipsometry studies with FTIR. With a giant birefringence Δn ∼ 0.9, BaTiSe3 emerges as a new candidate for miniaturized birefringent optics for mid‐wave infrared to long‐wave infrared imaging.
Source: Advanced Optical Materials
Language: English
Field: Materials Science
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $4,650
Funders: National Science Foundation, U.S. Department of Energy, Gordon and Betty Moore Foundation, University of Southern California, Chinese Academy of Sciences, Office of Science, Multidisciplinary University Research Initiative, Viterbi School of Engineering, University of Southern California, Office of Naval Research, Division of Materials Research, Division of Chemistry, Basic Energy Sciences, Army Research Office
Awards: G1432373144, G154838592, G1638050999, NSF's ChemMatCARS: A synchrotron X-ray national facility for chemistry and materials research at the Advanced Photon Source, G2170237165, G222768804, G2278757305, G3511855645, ULTRAFAST ELECTRONIC AND STRUCTURAL DYNAMICS IN COMPLEX MATERIALS, G4083895281, G42916606, Collaborative Research: Revealing the Role of Structural Modulations on the Electronic Properties of Hexagonal Chalcogenide Perovskite Semiconductors, G4985909365, G5585513702, G5648016710, CAREER: FRACTAL ELECTRONIC TEXTURES IN QUANTUM CRITICAL SOLIDS, Wisconsin Materials Research Science and Engineering Center, MRI: Acquisition of an X-ray Diffractometer at the University of Southern California, G7452299184, Nuh Gedik Experimental Investigator Award, G8876996369
OpenAlex ID: W4402173765