Université de Fribourg

Probing intraband excitations in ${\mathrm{ZrTe}}_{5}$: A high-pressure infrared and transport study

Santos-Cottin, D. ; Padlewski, M. ; Martino, E. ; David, S. Ben ; Mardelé, F. Le ; Capitani, F. ; Borondics, F. ; Bachmann, M. D. ; Putzke, C. ; Moll, P. J. W. ; Zhong, R. D. ; Gu, G. D. ; Berger, H. ; Orlita, M. ; Homes, C. C. ; Rukelj, Z. ; Akrap, Ana

In: Physical Review B, 2020, vol. 101, no. 12, p. 125205

Zirconium pentatetelluride, ZrTe5, shows remarkable sensitivity to hydrostatic pressure. In this work we address the high-pressure transport and optical properties of this compound, on samples grown by flux and chemical vapor transport. The high-pressure resistivity is measured up to 2 GPa, and the infrared transmission up to 9 GPa. The dc conductivity anisotropy is determined using a...

Université de Fribourg

Optical excitations in Sr₂CuO₃

Kim, Kyung Wan ; Gu, G. D.

In: Physical Review B, 2009, vol. 79, no. 8, p. 085121

We investigated excitation spectra of the one-dimensional chain compound Sr₂CuO₃. The small peak at 2.3 eV in the loss function turned out to correspond to the strong charge-transfer transition at 1.8 eV in conductivity. It has the excitonic character expected in one-dimensional extended Hubbard model of the transition from the lower Hubbard band to the Zhang-Rice singlet state. The strongest...

Université de Fribourg

Bound Excitons in Sr₂CuO₃

Kim, Kyung Wan ; Gu, G. D. ; Homes, C. C. ; Noh, T. W.

In: Physical Review Letters, 2008, vol. 101, no. 17, p. 177404

We investigated temperature dependent optical spectra of the one-dimensional chain compound Sr₂CuO₃. The charge transfer transition polarized along the chain direction shows a strongly asymmetric line shape as expected in one-dimensional extended Hubbard model. At low temperature, the charge transfer peak shows a large blueshift and reveals additional sharp peaks at the gap. Even though many...