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arXiv · 1206.5905

Non-unitary triplet pairing in the centrosymmetric superconductor LaNiGa$_2$

A. D. Hillier·J. Quintanilla·B. Mazidian·J. F. Annett·R. Cywinski
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Abstract

Muon spin rotation and relaxation experiments on the centrosymmetric intermetallic superconductor LaNiGa$_2$ are reported. The appearance of spontaneous magnetic fields coincides with the onset of superconductivity, implying that the superconducting state breaks time reversal symmetry, similarly to non-centrosymmetric LaNiC$_2$. Only four triplet states are compatible with this observation, all of which are non-unitary triplets. This suggests that LaNiGa$_2$ is the centrosymmetric analogue of LaNiC$_2$. We argue that these materials are representatives of a new family of paramagnetic non-unitary superconductors.

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A. D. Hillier, J. Quintanilla, B. Mazidian, J. F. Annett, R. Cywinski. 2012-06-26. Non-unitary triplet pairing in the centrosymmetric superconductor LaNiGa$_2$. https://doi.org/10.1103/physrevlett.109.097001

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