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arXiv · 1802.08268

Odd-frequency Pairing in the Edge States of Superconducting Pnictides in the Coexistence Phase with Antiferromagnetism

Cody Youmans·Areg Ghazaryan·Mehdi Kargarian·Pouyan Ghaemi
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Abstract

In several members of the pnictide materials, spin density wave order coexists with superconductivity over a range of dopings and temperature. In this paper we show that odd-frequency superconductivity emerges on the edges of pnictides in such a coexistence phase. In particular, the breaking of spin-rotation symmetry by SDW and translation symmetry by the edge can lead to the development of odd-frequency spin-triplet Cooper pairing on edges of superconducting pnictide samples. In this case, the odd-frequency pairing has even parity components, which are immune to disorder. Our results show that pnictides are a natural platform to realize odd frequency superconductivity, which is a new quantum phase and has been mainly searched for in heterostructures of magnetic and superconducting materials. The emergence of odd-frequency pairing on the edges and in the defects can be potentially detected in magnetic response measurements.

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Cody Youmans, Areg Ghazaryan, Mehdi Kargarian, Pouyan Ghaemi. 2018-11-08. Odd-frequency Pairing in the Edge States of Superconducting Pnictides in the Coexistence Phase with Antiferromagnetism. https://doi.org/10.1103/physrevb.98.144517

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