Onset and melting of local orbital order

Dheeraj Kumar Singh; Avinash Singh

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arXiv · 1010.4424

Onset and melting of local orbital order

Dheeraj Kumar Singh·Avinash Singh

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Abstract

The onset and melting of locally staggered charge/orbital correlations is investigated within a two-orbital correlated electron model with inter-orbital and inter-site Coulomb interactions. Beyond the critical doping concentration x_c ~ 0.2, the (pi,pi,pi) staggered orbital order in the ferromagnet is found to be stabilized at finite temperature. The CE-type orbital correlation exhibits a sharp onset close to the Curie temperature and rapid thermal melting, which provides quantitative understanding of the (pi/2,pi/2,0) feature observed near T_c in neutron scattering experiments. In the zig-zag AF state, the CE-type orbital correlations are found to be even more readily stabilized, but only within a narrow doping regime around x=0.5.

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Dheeraj Kumar Singh, Avinash Singh. 2010-12-05. Onset and melting of local orbital order. https://arxiv.org/abs/1010.4424

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