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arXiv · 1908.04820

Detecting non-unitary multiorbital superconductivity with Dirac points at finite energies

J. L. Lado·M. Sigrist
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Abstract

Determining the symmetry of the order parameter of unconventional superconductors remains a recurrent topic and non-trivial task in the field of strongly correlated electron systems. Here we show that the behavior of Dirac points away from the Fermi energy is a potential tool to unveil the orbital structure of a superconducting state. In particular, we show that gap openings in such Dirac crossings are a signature of non-unitary multiorbital superconducting order. Consequently, also spectral features at higher energy can help us to identify broken symmetries of superconducting phases and the orbital structure of non-unitary states. Our results show how angle-resolved photo-emission spectroscopy measurements can be used to detect non-unitary multiorbital superconductivity.

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J. L. Lado, M. Sigrist. 2019-08-13. Detecting non-unitary multiorbital superconductivity with Dirac points at finite energies. https://doi.org/10.1103/physrevresearch.1.033107

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