Possible pressure-induced insulator-to-metal transition in low-dimensionalTiOCl

Mott-Hubbard gap closure and structural phase transition in the oxyhalides TiOBr and TiOCl under pressure

“…7,15 For the reflectance measurements finely ground CsI powder was chosen as pressure medium to insure direct contact of the sample with the diamond window.…”

“…The 3d electrons are localized due to strong electronic correlations, and hence TiOBr and TiOCl are MottHubbard insulators, with a charge gap of ≈2 eV. 6,7,8 It was predicted that these materials exhibit a resonating valence bond state and high-temperature superconductivity upon doping. 9,10 However, up to now a metallization of TiOX upon doping could not be achieved.…”

Symmetry disquisition on theTiOXphase diagram(X=Br,Cl)Fausti1, Lummen2, Angelescu3 et al. 2007Phys. Rev. B264271View full textAdd to dashboardCite

“…[14][15][16][17] Moreover, the presence of a pressure induced metal to insulator transition has been recently suggested for TiOCl. 18 Due to this complex phase behavior, both TiOCl and TiOBr have been extensively discussed in recent literature, and various questions still remain open: there is no agreement on the crystal symmetry of the spin Peierls phase, the nature and symmetry of the incommensurate phase are not clear, and the anomalous first-order character of the transition to the spin-Peierls state is not explained.…”

Suppression of the charge-density-wave state inSr10Ca4Cu24Kuntscher1, Huber2, Hücker3 2014Phys. Rev. BSelf Cite

“…31,32 For the KK analysis the reflectivity spectra were fitted with the Drude-Lorentz model, in order to extrapolate the missing low-and high-frequency parts of the spectra. Hereby, the dc resistivity data of Sr 11 Ca 3 Cu 24 O 41 for E c in Ref.…”