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arXiv · 1701.08352

Spin-triplet $f$-wave symmetry in superconducting monolayer $MoS_2$

Abstract

The proximity-induced spin-triplet $f$-wave symmetry pairing in a monolayer molybdenum disulfide-superconductor hybrid features an interesting electron-hole excitations and also effective superconducting subgap, giving rise to a distinct Andreev resonance state. Owing to the complicated Fermi surface and momentum dependency of $f$-wave pair potential, monolayer $MoS_2$ with strong spin-orbit coupling can be considered an intriguing structure to reveal the superconducting state. Actually, this can be possible by calculating the peculiar spin-valley polarized transport of quasiparticles in a related normal metal/superconductor junction. We theoretically study the formation of effective gap at the interface and resulting normalized conductance on top of a $MoS_2$ under induction of $f$-wave order parameter, using Bloder-Tinkham-Klapwijk formalism. The superconducting excitations shows that the gap is renormalized by a \textit{bias limitation} coefficient including dynamical band parameters of monolayer $MoS_2$, especially, ones related to the Schrodinger-type momentum of Hamiltonian. The effective gap is more sensitive to the n-doping regime of superconductor region. The signature of spin-orbit coupling, topological and asymmetry mass-related terms in the resulting subgap conductance and, in particular, maximum conductance is presented. In the absence of topological term, the effective gap reaches to its maximum value. The unconventional nature of superconducting order leads to the appearance of zero-bias conductance. In addition, the maximum value of conductance can be controlled by tuning the doping level of normal and superconductor regions.

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Hadi Goudarzi, Maryam Khezerlou, Hasan Sedghi, Afifeh Ghorbai. 2017-01-29. Spin-triplet $f$-wave symmetry in superconducting monolayer $MoS_2$. https://doi.org/10.1016/j.spmi.2017.02.005

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