Superconducting dome driven by intervalley phonon scattering in monolayer MoS₂

Abstract

We combine first-principles calculations, a three-band tight-binding model, and Bardeen-Cooper-Schrieffer theory to explore the physical mechanism for a dome-shaped dependence of superconducting transition temperature of monolayer MoS 2 on electron doping concentration, which has been observed experimentally (2012 Science 338 1193). We find that in the process of doping more electrons contribute to superconducting pairing, but above some doping value the effective attractive interaction decreases so greatly that it starts to reduce the pairing strength, forming a superconducting dome. Therefore, the dome behavior can be attributed to the competition between the growing Fermi pocket (corresponding to an increase of the number of intervalley phonon scatterings) and the screened intervalley phonon scattering (corresponding to a decrease of scattering probability).

Reduced ITO for transparent superconducting electronics

“…The as-received films were not superconducting, but all the electrochemically reduced films we tested, ranging from 16 mC • cm −2 to 110 mC • cm −2 , exhibited superconducting transitions. Our results, shown in figure 1(a), were consistent with a domeshaped dependence of transition temperature on reduction charge density as reported by others in ITO [16] and in line with the behavior of several other superconducting doped semiconductors [22][23][24][25]. The maximum transition temperature observed was 4 K in a sample reduced to about 60 mC • cm −2 .…”

Superconductivity in Mo–P compounds under pressure and in double-Weyl semimetal Hex-MoP2

“…First, based on orbitals {d xy , d x 2 – y 2 , d z 2 } of Mo atoms, 62–64 we build the three-band TBM via considering the nearest-neighbor hopping (NNP) in plane and next-NNP out of plane. The matrix elements of the Hamiltonian are given by , in which is the hopping integral between the different atomic orbitals.…”