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arXiv · 1211.5280

Peculiarities of length scales in a two-orbital superconductor

G. Litak·T. Örd·K. Rägo·A. Vargunin
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Abstract

We study the spatial behaviour of coherency and magnetic field in a two-orbital superconductor. The superconducting phase transition is caused here by the on-site intra-orbital attractions (negative-U Hubbard model) and inter-orbital pair-transfer interaction. We find the critical (diverging at $T_{c}$) and non-critical (remaining finite) coherence lengths and magnetic field penetration depth for various values of hopping integrals and the strengths of intra-orbital attractions. Numerical results have been obtained for a two-dimensional square lattice.

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G. Litak, T. Örd, K. Rägo, A. Vargunin. 2012-11-22. Peculiarities of length scales in a two-orbital superconductor. https://arxiv.org/abs/1211.5280

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