Portal de Periódicos da CAPES

Raman Scattering in the Mott Insulators LaTiO 3 and YTiO 3 : Evidence for Orbital Excitations

2006; American Physical Society; Volume: 97; Issue: 15 Linguagem: Inglês

10.1103/physrevlett.97.157401

1092-0145

C. Ulrich, A. Gößling, M. Grüninger, Maël Guennou, Heinz D. Roth, M. Cwik, T. Lorenz, Giniyat Khaliullin, B. Keimer,

Advanced Condensed Matter Physics

Raman scattering is used to observe pronounced electronic excitations around 230 meV--well above the two-phonon range--in the Mott insulators LaTiO3 and YTiO3. Based on the temperature, polarization, and photon energy dependence, the modes are identified as orbital excitations. The observed profiles bear a striking resemblance to magnetic Raman modes in the insulating parent compounds of the superconducting cuprates, indicating an unanticipated universality of the electronic excitations in transition metal oxides.