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arXiv · 2210.16235

Interplay of Hidden Orbital Order and Superconductivity in CeCoIn5

Abstract

Visualizing atomic-orbital degrees of freedom is a frontier challenge in scanned microscopy. Some types of orbital order are virtually imperceptible to normal scattering techniques because they do not reduce the overall crystal lattice symmetry. A good example is dxz/dyz ({\pi},{\pi}) orbital order in tetragonal lattices. For enhanced detectability, here we consider the quasiparticle scattering interference (QPI) signature of such ({\pi},{\pi}) orbital order in both normal and superconducting phases. The theory reveals that sublattice-specific QPI signatures generated by the orbital order should emerge strongly in the superconducting phase. Sublattice-resolved QPI visualization in superconducting CeCoIn5 then reveals two orthogonal QPI patterns at lattice-substitutional impurity atoms. We analyze the energy dependence of these two orthogonal QPI patterns and find the intensity peaked near E=0, as predicted when such ({\pi}) orbital order is inte,{\pi}rtwined with d-wave superconductivity. Sublattice-resolved superconductive QPI techniques thus represent a new approach for study of hidden orbital order.

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Weijiong Chen, Clara Neerup Breiø, Freek Massee, M. P. Allan, C. Petrovic, J. C. Séamus Davis, P. J. Hirschfeld, Brian M. Andersen, Andreas Kreisel. 2022-10-28. Interplay of Hidden Orbital Order and Superconductivity in CeCoIn5. https://doi.org/10.1038/s41467-023-38760-7

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