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arXiv · 1112.5003

Signature of antiferromagnetic long-range order in the optical spectrum of strongly correlated electron systems

C. Taranto·G. Sangiovanni·K. Held·M. Capone·A. Georges·A. Toschi
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Abstract

We show how the onset of a non-Slater antiferromagnetic ordering in a correlated material can be detected by optical spectroscopy. Using dynamical mean-field theory we identify two distinctive features: The antiferromagnetic ordering is associated with an enhanced spectral weight above the optical gap, and well separated spin-polaron peaks emerge in the optical spectrum. Both features are indeed observed in LaSrMnO_4 [Gössling et al., Phys. Rev. B 77, 035109 (2008)]

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C. Taranto, G. Sangiovanni, K. Held, M. Capone, A. Georges, A. Toschi. 2011-12-21. Signature of antiferromagnetic long-range order in the optical spectrum of strongly correlated electron systems. https://doi.org/10.1103/physrevb.85.085124

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