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Effect of Crystal Structure to Resonant X-Ray Scattering on YTiO3

Manabu Takahashi·Jun-ichi Igarashi
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Abstract

We investigate the mechanism of the resonant X-ray scattering on the Ti $K$ edge region of YTiO$_3$ using the band structure calculation combined with the local density approximation. A large intensity is obtained for the orbital superlattice spots. The calculated spectra consist of several peaks as a function of photon energy in agreement with the recent experiments. Against a naive interpretation that directly relates the intensity to the orbitally polarized $3d$ states, the obtained large intensity arises from the distorted crystal structure, i.e., the tilt of the TiO$_6$ octahedra and the Jahn-Teller distortion, which considerably modifies the $4p$ states in the intermediate states of the dipolar process. This casts doubt on a prevailing assertion that the resonant x-ray scattering is a direct observation of the orbital order.

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Manabu Takahashi, Jun-ichi Igarashi. 2001-04-25. Effect of Crystal Structure to Resonant X-Ray Scattering on YTiO3. https://arxiv.org/abs/cond-mat/0104480

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