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arXiv · 1210.7310

Resolution of Entropy $\ln \sqrt 2$ by Ordering in Two-Channel Kondo Lattice

Shintaro Hoshino·Junya Otsuki·Yoshio Kuramoto
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Abstract

Peculiar property of electronic order is clarified for the two-channel Kondo lattice. With two conduction electrons per site, the order parameter is a composite quantity involving both local and itinerant degrees of freedom. In contrast to the ordinary Kondo lattice, a heavy electron band is absent above the transition temperature, but is rapidly formed below it. The change of entropy associated with the ordering is found to be close to $\ln \sqrt 2$ per site. This entropy corresponds to the residual entropy in a two-channel Kondo impurity, which has been regarded as due to localized free Majorana particles. The present composite order is interpreted as instability of Majorana particles toward non-Kramers conduction electrons plus heavy fermions that involve localized electrons.

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Shintaro Hoshino, Junya Otsuki, Yoshio Kuramoto. 2012-10-27. Resolution of Entropy $\ln \sqrt 2$ by Ordering in Two-Channel Kondo Lattice. https://doi.org/10.7566/jpsj.82.044707

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