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Orbital excitations in titanates

C. Ulrich·A. Gössling·M. Grüninger·M. Guennou·H. Roth·M. Cwik·T. Lorenz·G. Khaliullin·B. Keimer
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Abstract

Raman scattering is used to observe pronounced electronic excitations around 230 meV - well above the two-phonon range - in the Mott insulators LaTiO$_3$ and YTiO$_3$. 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.

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C. Ulrich, A. Gössling, M. Grüninger, M. Guennou, H. Roth, M. Cwik, T. Lorenz, G. Khaliullin, B. Keimer. 2005-03-04. Orbital excitations in titanates. https://arxiv.org/abs/cond-mat/0503106

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