Theory of superconductivity in hole-doped monolayer MoS${}_2$

Abstract

We theoretically investigate the Cooper-pair symmetry to be realized in hole-doped monolayer MoS${}_2$ by solving linearized BCS gap equations on the three-orbital attractive Hubbard-like model in the presence of the atomic spin-orbit coupling. In hole-doped monolayer MoS${}_2$, both spin-orbit coupling and the multi-orbital effects are more prominent than those of electron-doped system. Near the valence band edge, the Fermi surfaces are composed of three different types of hole pockets, namely, one mainly consisting of the almost spin-degenerate $|d_{z^2}⟩$ orbital near $\Gamma$ point, and the others of the spin-split upper and lower bands near $\mathrm{K}$ and ${\mathrm{K}}^{\prime }$ points arising from the $|d_{x^2-y^2}⟩$ and $|d_{xy}⟩$ orbitals. The number of relevant Fermi pockets increases with increase of the doping. At very low doping, the upper split bands of $|d_{x^2-y^2}⟩$ and $|d_{xy}⟩$ are concerned, yielding extremely low $T_{\mathrm{c}}$ due to small density of states of the split bands. For further doping, the conventional spin-singlet state (SS) appears in the $\Gamma$ pocket, which has a mixture of the spin-triplet (orbital-singlet) (ST-OS) and spin-singlet (orbital-triplet) (SS-OT) states in the K and K${}^{\prime }$ pockets. The ratio of the mixture depends on the relative strength of the interactions, and the sign of the exchange interactions. Moderately strong ferromagnetic exchange interactions even lead to the pairing state with the dominant ST-OS state over the conventional SS one. With these observations, we expect that the fascinating pairing with relatively high $T_{\mathrm{c}}$ emerges at high doping that involves all the three Fermi pockets.

arXiv comment8 pages, 4 figures

References in corpus (39)

• Atomically thin MoS2: A new direct-gap semiconductor
• Coupled spin and valley physics in monolayers of MoS2 and other group-VI dichalcogenides
• Control of valley polarization in monolayer MoS2 by optical helicity
• Valley polarization in MoS2 monolayers by optical pumping
• MoS_2 as an ideal material for valleytronics: valley-selective circular dichroism and valley Hall effect
• The Valley Hall Effect in MoS2 Transistors
• Evidence of Ising pairing in superconducting NbSe${}_2$ atomic layers
• Heavy fermion superconductivity and magnetic order in non-centrosymmetric $CeP{t}_{3}Si$
• Optical signature of symmetry variations and spin-valley coupling in atomically thin tungsten dichalcogenides
• Three-band tight-binding model for monolayers of group-VIB transition metal dichalcogenides
• Superconducting 2D system with lifted spin degeneracy: Mixed singlet-triplet state
• Two Dimensional Ising Superconductivity in Gated MoS${}_2$
• Superconductivty without inversion symmetry: MnSi versus CePt_3Si
• Electrical Tuning of Valley Magnetic Moment via Symmetry Control
• Superconductivity protected by spin-valley locking in ion-gated MoS2
• Superconductivity and spin-orbit coupling in non-centrosymmetric materials: a review
• Effect of spin-orbit interaction on the excitonic effects in single-layer, double-layer, and bulk MoS2
• Monolayer MoS2: trigonal warping, "Γ-valley", and spin-orbit coupling effects
• Tight-binding model and direct-gap/indirect-gap transition in single-layer and multi-layer MoS${}_2$
• Tuning Ising superconductivity with layer and spin-orbit coupling in two-dimensional transition-metal dichalcogenides
• Magnetoelectric effects and valley controlled spin quantum gates in transition metal dichalcogenide bilayers
• Transport Theory of Monolayer Transition-Metal Dichalcogenides through Symmetry
• Topological superconductivity in monolayer transition metal dichalcogenides
• Effective lattice Hamiltonian for monolayer MoS2 : Tailoring electronic structure with perpendicular electric and magnetic fields
• Possible Topological Superconducting Phases of MoS${}_2$
• Magnetic Field Driven Nodal Topological Superconductivity in Monolayer Transition Metal Dichalcogenides
• Unified understanding of superconductivity and Mott transition in alkali-doped fullerides from first principles
• Spin- and valley-dependent magneto-optical properties of MoS2
• Interactions and superconductivity in heavily doped MoS2
• Ab initio derivation of electronic low-energy models for C60 and aromatic compounds
• Phase Diagram of Electron Doped Dichalcogenides
• Ab initio downfolding for electron-phonon coupled systems: constrained density-functional perturbation theory (cDFPT)
• Enhancement of the upper critical field in disordered transition metal dichalcogenide monolayers
• Odd-parity superconductivity in bilayer transition metal dichalcogenides
• Superconducting dome in MoS2 and TiSe2 generated by quasiparticle-phonon coupling
• Valley- and spin-switch effects in molybdenum disulfide superconducting spin valve
• Unconventional superconductivity from magnetism in transition metal dichalcogenide
• Unconventional superconductivity and anomalous response in hole-doped transition metal dichalcogenides
• Triplet pairing driven by Hund's coupling in doped monolayer MoS${}_2$

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• Robustness of unconventional $s$-wave superconducting states against disorder
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