Magnetic impurities make superconductivity in 3D Dirac semi-metal triplet

Abstract

Conventional electron-phonon coupling induces either odd (triplet) or even (singlet) pairing states in a time reversal and inversion invariant Dirac semi - metal. In certain range of the chemical potential $\mu$ and parameters characterizing the pairing attraction (effective electron-electron coupling constant $\lambda$ and the Debye energy $T_D$) the energy of the singlet although always lower, prevails by a very slim margin over the triplet. This means that interactions that are small but discriminate between the spin singlet and the spin triplet determine the nature of the superconducting order there. It shown that in materials close enough to the Dirac point ($\mu \lesssim T_D$) magnetic impurities stabilize the odd pairing superconducting state.

5 pages, 4 figures.Supplemenatry materials, 5 pages, 2 figures. arXiv admin note: substantial text overlap with arXiv:1407.0770

References in corpus (6)

• Bulk Band Gap and Surface State Conduction Observed in Voltage-Tuned Crystals of the Topological Insulator Bi${}_2$Se${}_3$
• Electron-phonon Coupling on the Surface of the Topological Insulator Bi2Se3: Determined from Surface Phonon Dispersion Measurements
• Time-reversal invariant topological superconductivity in doped Weyl semimetals
• Quantum superconducting criticality in graphene and topological insulators
• Interband Effects of Magnetic Field on Hall Effects for Dirac Electrons in Bismuth
• Pairing symmetry and vortex zero-mode for superconducting Dirac fermions