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arXiv · 1109.0234

Evidence for charge and orbital order in the doped titanates RE_(1-x)Ca_xTiO_3 (RE=Y, Er, Lu)

A. C. Komarek·M. Reuther·T. Lorenz·A. Cousson·P. Link·W. Morgenroth·D. Trots·C. Baehtz·M. Braden
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Abstract

Combining macroscopic and diffraction methods we have studied the electric, magnetic and struc- tural properties of RE_(1-x)Ca_xTiO_3 (RE=Y, Er, Lu) focusing on the concentration range near the metal-insulator transition. The insulating phase, which is stabilized by a smaller rare-earth ionic ra- dius, exhibits charge order with a predominant occupation of the dxy orbital. The charge and orbital ordering explains the broad stability range of the insulating state in RE_(1-x)Ca_xTiO_3 with smaller rare-earth ions. The strong modulation of the Ti-O bond distances indicates sizeable modulation of the electric charge.

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A. C. Komarek, M. Reuther, T. Lorenz, A. Cousson, P. Link, W. Morgenroth, D. Trots, C. Baehtz, M. Braden. 2011-09-01. Evidence for charge and orbital order in the doped titanates RE_(1-x)Ca_xTiO_3 (RE=Y, Er, Lu). https://arxiv.org/abs/1109.0234

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