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Determination of the orbital moment and crystal field splitting in LaTiO$_{3}$

M. W. Haverkort·Z. Hu·A. Tanaka·G. Ghiringhelli·H. Roth·M. Cwik·T. Lorenz·C. Schuessler-Langeheine·S. V. Streltsov·A. S. Mylnikova·V. I. Anisimov·C. de Nadai·N. B. Brookes·H. H. Hsieh·H. -J. Lin·C. T. Chen·T. Mizokawa·Y. Taguchi·Y. Tokura·D. I. Khomskii·L. H. Tjeng
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Abstract

Utilizing a sum-rule in a spin-resolved photoelectron spectroscopic experiment with circularly polarized light, we show that the orbital moment in LaTiO$_3$ is strongly reduced both below and above the Néel temperature. Using Ti $L_{2,3}$ x-ray absorption spectroscopy as a local probe, we found that the crystal field splitting in the $t_{2g}$ subshell is about 0.12-0.30 eV. This large splitting does not facilitate the formation of an orbital liquid.

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M. W. Haverkort, Z. Hu, A. Tanaka, G. Ghiringhelli, H. Roth, M. Cwik, T. Lorenz, C. Schuessler-Langeheine, S. V. Streltsov, A. S. Mylnikova, V. I. Anisimov, C. de Nadai, N. B. Brookes, H. H. Hsieh, H. -J. Lin, C. T. Chen, T. Mizokawa, Y. Taguchi, Y. Tokura, D. I. Khomskii, L. H. Tjeng. 2004-09-23. Determination of the orbital moment and crystal field splitting in LaTiO$_{3}$. https://doi.org/10.1103/physrevlett.94.056401

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