Pressure-induced metallization and structural phase transition of the Mott-Hubbard insulator TiOBr

Abstract

We investigated the pressure-dependent optical response of the low-dimensional Mott-Hubbard insulator TiOBr by transmittance and reflectance measurements in the infrared and visible frequency range. A suppression of the transmittance above a critical pressure and a concomitant increase of the reflectance are observed, suggesting a pressure-induced metallization of TiOBr. The metallic phase of TiOBr at high pressure is confirmed by the presence of additional excitations extending down to the far-infrared range. The pressure-induced metallization coincides with a structural phase transition, according to the results of x-ray powder diffraction experiments under pressure.

4 pages, 3 figures

References in corpus (7)

• Spin-Peierls transition in TiOCl
• Zero-field incommensurate spin-Peierls phase with interchain frustration in TiOCl
• Optical study of orbital excitations in transition-metal oxides
• Incommensurate interactions and non-conventional spin-Peierls transition in TiOBr
• Pressure-induced insulator-to-metal transition in low-dimensional TiOCl
• Symmetry disquisition on the TiOX phase diagram
• Effect of pressure on the polarized infrared optical response of quasi-one-dimensional LaTiO${}_{3.41}$

Cited by in corpus (6)

• Infrared and Terahertz Spectroscopy of Strongly Correlated Electron Systems under Extreme Conditions
• Enhanced dimerization of TiOCl under pressure: spin-Peierls - to - Peierls transition
• Mott-Hubbard gap closure and structural phase transition in the oxyhalides TiOBr and TiOCl under pressure
• Two pressure-induced structural phase transitions in TiOCl
• High pressure x-ray study of spin-Peierls physics in the quantum spin chain material TiOCl
• Novel electronic states close to Mott transition in low-dimensional and frustrated systems