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arXiv · 1607.07930

Theory of Orbital Susceptibility on Excitonic Insulator

Hiroyasu Matsuura·Masao Ogata
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Abstract

We study the temperature dependence of the orbital susceptibility of an excitonic insulator on the basis of a two-band model. It is shown that a drastic change (an anomalous enhancement) in susceptibility as a function of temperature occurs owing to the occurrence of additional orbital susceptibility due to the excitonic gap. We calculate explicitly the temperature dependence of orbital susceptibility for a model of Ta$_2$NiSe$_5$, and show that the result is consistent with experimental results.

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Hiroyasu Matsuura, Masao Ogata. 2016-07-27. Theory of Orbital Susceptibility on Excitonic Insulator. https://doi.org/10.7566/jpsj.85.093701

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