A simple tight-binding approach to topological superconductivity in monolayer MoS₂

Abstract

Monolayer molybdenum disulfide (MoS2) has a honeycomb crystal structure. Here, with considering the triangular sublattice of molybdenum atoms, a simple tight-binding Hamiltonian is introduced (derived) for studying the phase transition and topological superconductivity in MoS2 under uniaxial strain. It is shown that spin-singlet p + ip wave phase is a topological superconducting phase with nonzero Chern numbers. When the chemical potential is greater (smaller) than the spin-orbit coupling (SOC) strength, the Chern number is equal to four (two) and otherwise it is equal to zero. Also, the results show that, if the superconductivity energy gap is smaller than the SOC strength and the chemical potential is greater than the SOC strength, the zero energy Majorana states exist. Finally, we show the topological superconducting phase is preserved under uniaxial strain.

Superconductivity in CuIr 2–x Al x Te4 telluride chalcogenides

“…Low-dimensional layered transition metal dichalcogenides (TMDs) are other opportune material platforms for the exploration of various quantum instabilities, [12][13][14][15][16][17][18][19][20][21] especially the interplay between SC and CDW, in which the CDW order refers to condensate with periodic modulations of the crystalline lattice and conduction electron density in real space. Typically, the SC can be induced and a dome-shape superconducting phase diagram is formed upon suppressing the CDW order, [22][23][24][25][26][27] which is highly similar to the phase diagrams of unconventional high-T c cuprates and iron-based supercon-ductors.…”

Magnetic‐Field Regulation of Nodal Topological Superconducting States in Monolayer Ising Superconductor NbSe2

“…A Majorana fermion is different from the traditional fermion in that it is an antiparticle of itself and follows non-Abelian statistics. [8,9] Topological superconductors can be classified into two categories, namely nodeless (gapped) topological superconductors and NTSCs. The formation of a fully gapped topological superconductor has three possible routes, namely the construction of an s-wave superconductor/topological insulator heterostructure, the construction of a self-proximityinduced Fe-based topological superconductor, and the construction of an inherently unconventional superconductor with oddparity p þ ip pairing.…”

Surface structure modification of ReSe2 nanosheets via carbon ion irradiation

“…Owing to the unique optical and electronic properties, transition metal dichalcogenides (TMDs) have been widely studied, showing that TMD has a great potential application in beyond-CMOS devices. [1][2][3][4][5][6][7][8] Among the TMDs, ReSe 2 crystallizes belong to the triclinic system, and the cluster of Re 4 units forms a one-dimensional (1D) chain inside each monolayer, with layers held together by van der Waals attraction. [9] Generally, most VI TMDs such as MoS 2 and WS 2 show more superior performances due to their monolayer structure, while unlike other two-dimensional (2D) materials, ReSe 2 shows very weak layer-dependent optical and vibrational properties.…”