Odd-frequency spin-triplet pairing states in half-metal/d-wave superconductor junctions

Based on the extended Blonder–Tinkham–Klapwijk formalism, differential conductance spectrum of d-wave superconductor/half-metal junctions is investigated as a function of the interfacial spin–orbit coupling (SOC). It shows that the SOC modifies the interfacial spin-flip scattering, enabling spin-singlet and spin-triplet pairing conversion with the aid of equal-spin-band Andreev reflection. A zero-bias conductance peak has been found, which is closely related to the zero energy Andreev bound state of equal-spin pairing correlation induced by the broken electron-hole symmetry of model Hamiltonian and gives strong evidences for the odd-frequency spin-triplet pairing states.

► Conductance spectrum of d-wave superconductor/half-metal junctions is investigated.
► Zero-energy conductance peak exists due to the breaking of electron-hole symmetry.
► It provides strong evidences for the odd frequency equal-spin-triplet pairing state.