Mapping of Electron-Hole Excitations in the Charge-Density-Wave System 1T-TiSe2 Using Resonant Inelastic X-Ray Scattering

Claude Monney (1) , K.J. Zhou (1, 2) , Hervé Cercellier (3) , Z. Vydrova (4) , Michael Gunnar Garnier (4) , G. Monney (4) , V. N. Strocov (5) , Helmut Berger (6) , Hans Beck (4) , T. Schmitt (5) , Philipp Aebi (4)

1 SLS-PSI - The Swiss Light Source (SLS)
2 DIAMOND Light source
3 NEEL - MagSup - Magnétisme et Supraconductivité
4 UNIFR - Université de Fribourg = University of Fribourg
5 PSI - Paul Scherrer Institute
6 EPFL - Ecole Polytechnique Fédérale de Lausanne

In high-resolution resonant inelastic x-ray scattering at the Ti L edge of the charge-density-wave system 1T-TiSe2, we observe sharp low energy loss peaks from electron-hole pair excitations developing at low temperature. These excitations are strongly dispersing as a function of the transferred momentum of light. We show that the unoccupied bands close to the Fermi level can effectively be probed in this broadband material. Furthermore, we extract the order parameter of the charge-density-wave phase from temperature-dependent measurements.

Domaines: Electrons fortement corrélés [cond-mat.str-el]

Claude Monney, K.J. Zhou, Hervé Cercellier, Z. Vydrova, Michael Gunnar Garnier, et al.. Mapping of Electron-Hole Excitations in the Charge-Density-Wave System 1T-TiSe2 Using Resonant Inelastic X-Ray Scattering. Physical Review Letters, 2012, 109 (4), pp.047401. ⟨10.1103/PhysRevLett.109.047401⟩. ⟨hal-00966360⟩