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arXiv · 1309.5719

Superconductivity of Composite Particles in Two-Channel Kondo Lattice

Shintaro Hoshino·Yoshio Kuramoto
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Abstract

Emergence of odd-frequency s-wave superconductivity is demonstrated in the two-channel Kondo lattice by means of the dynamical mean-field theory combined with the continuous-time quantum Monte Carlo method. Around half filling of the conduction bands, divergence of an odd-frequency pairing susceptibility is found, which signals instability toward the superconductivity. The corresponding order parameter is equivalent to a staggered composite-pair amplitude with even frequencies, which involves both localized spins and conduction electrons. A model wave function is constructed for the composite order with use of symmetry operations such as charge conjugation and channel rotations. Given a certain asymmetry of the conduction bands, another s-wave superconductivity is found that has a uniform order parameter. The Kondo effect in the presence of two channels is essential for both types of unconventional superconductivity.

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Shintaro Hoshino, Yoshio Kuramoto. 2013-09-23. Superconductivity of Composite Particles in Two-Channel Kondo Lattice. https://doi.org/10.1103/physrevlett.112.167204

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