The quantum transport properties of graphene and monolayer M oS 2 superconductor heterostructures has been of considerable importance in the recent few years. Layered nature of molybdenum disulfide permits the superconducting correlation induction. Moreover, peculiar dynamical features of monolayer M oS 2 , such as valence band spin-splitting in the nondegenerate K and K ′ valleys originated from strong spin-orbit coupling, and considerable direct band gap can make it potentially a useful material for electronics applications. Using the Dirac-like Hamiltonian of M oS 2 with taking into account the related mass asymmetry and topological contributions, we investigate the effect of spin-triplet p-wave pairing symmetry on the superconducting excitations, resulting in Andreev reflection process and Andreev bound state in the corresponding normal-superconductor (NS) and superconductor-normal-superconductor (SNS) structures, respectively. We study how the resulting subgap conductance and Josephson current are affected by the particular symmetry of order parameter. The signature of p x -wave symmetry is found to decline the subgap superconducting energy excitations and, consequently, slightly suppress the Andreev reflection in the case of p-doped S region. The essential dynamical parameters λ and β of M oS 2 have significant effect on the both tunneling conductance and Josephson current. Particularly, the considered p-wave symmetry in the superconducting bound energies may feature the zero energy states at the interfaces. The critical current oscillations as a function of length of junction are obtained in the p-doped S region. PACS: 73.63.-b; 74.45.+c; 72.25.-b So far in the literature, unconventional dand p-wave order parameter has much been studied in graphene, whereas a little attention has been paid to how unconventional pairing in monolayer M oS 2 influences the transport properties of related structures. Due to intrinsic massive Dirac gap (direct band gap of about 1.9 eV ), strong spin-orbit coupling (SOC) caused by dichalcogenide heavy transition metal atom and resulting two nondegenerate K and K ′ valleys relative to spin-up and spin-down quasiparticles at the valence band [35,36,37,38,39] (valley-contrasting spin-splitting 0.1 − 0.5 eV [3]) ML-MDS may exhibit dynamically new behaviors in the Andreev process [40,41] and superconducting Andreev states [42] at the interface of a normal-superconductor.In addition above dynamical peculiar properties of M oS 2 , its layered structure, chemical stability, and relatively high mobility (room temperature mobility over 200 cm 2 /V s) can make it potentially a useful material for electronics applications [5,43,44,45,46]. The spin-valve effect in proximity-induced ferromagnetic M oS 2 may result in a valley-spin-resolved conductance [47,48,49], which is considered as an essential feature for valleytronic devices [39,50,51]. Analogous to graphene, there is a valley index τ = ±1, which is robust against scattering by smooth deformations and long wavelength photons due to a ...

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Among the potential applications of topological insulators, we investigate theoretically the effect of coexistence of proximity-induced ferromagnetism and superconductivity on the surface states of 3-dimensional topological insulator, where the superconducting electron-hole excitations can be significantly affected by the magnetization of ferromagnetic order. We find that, Majorana mode energy, as a verified feature of TI F/S structure, along the interface sensitively depends on the magnitude of magnetization m zf s in FS region, while its slope in perpendicular incidence presents steep and no change. Since the superconducting gap is renormalized by a factor η(m zf s ), hence Andreev reflection is more or less suppressed, and, in particular, resulting subgap tunneling conductance is more sensitive to the magnitude of magnetizations in FS and F regions. Furthermore, an interesting scenario happens at the antiparallel configuration of magnetizations m zf and m zf s resulting in magnetoresistance in N/F/FS junction, which can be controlled and decreased by tuning the magnetization magnitude in FS region. : 74.45.+c; 85.75.-d; 73.20.-r PACS

The accurate and proper form of electron-hole excitations and corresponding Dirac-like spinors of monolayer molybdenum disulfide superconductor are exactly obtained. Andreev reflection and resulting subgap conductance in a M oS 2 -based ferromagnetic superconducting (F/S) junction is accurately investigated in terms of dynamical characteristics of system. Due to spin-splitting energy gap in the valence band and nondegenerate K and K ′ valleys, the ferromagnetic exchange energy σh can cause a distinct behavior of Andreev process between spin-up and spin-down charge carriers belonging to different valleys. The chemical potential is necessarily fixed by a determined range in order to occur the retro Andreev reflection. Given one-particle superconducting bispinors enable us to explicitly involve the anisotropic superconducting gap ∆ S under electron-hole conversion, i.e., taking place in d-wave pair coupling. The effect of such gap is exactly explained in terms of the dependence of the Andreev process on the electron incidence angle at the interface. PACS: 73.63.-b; 74.45.+c; 72.25.-b