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arXiv · 1110.4110

Topologically protected surface Majorana arcs and bulk Weyl fermions in ferromagnetic superconductors

Jay D. Sau·Sumanta Tewari
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Abstract

A number of ferromagnetic superconductors have been recently discovered which are believed to be in the so-called "equal spin pairing" (ESP) state. In the ESP state the Cooper pairs condense forming order parameters $\Delta_{\uparrow\uparrow}, \Delta_{\downarrow\downarrow}$ which are decoupled in the spin-sector. We show that these three-dimensional systems should generically support topologically protected surface Majorana arcs and bulk Weyl fermions as gapless excitations. Similar protected low-energy exotic quasiparticles should also appear in the recently discovered non-centrosymmteric superconductors in the presence of a Zeeman field. The protected surface arcs can be probed by angle-resolved photoemission (ARPES) as well as scanning tunneling microscope (STM) experiments.

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Jay D. Sau, Sumanta Tewari. 2011-10-18. Topologically protected surface Majorana arcs and bulk Weyl fermions in ferromagnetic superconductors. https://doi.org/10.1103/physrevb.86.104509

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