Manifestation of the odd-frequency spin-triplet pairing state in diffusive ferromagnet / superconductor junctions

Abstract

Using the quasiclassical Green's function formalism, we study the influence of the odd-frequency spin-triplet superconductivity on the local density of states (LDOS) in a diffusive ferromagnet (DF) attached to a superconductor. Various possible symmetry classes in a superconductor are considered which are consistent with the Pauli's principle: even-frequency spin-singlet even-parity (ESE) state, even-frequency spin-triplet odd-parity (ETO) state, odd-frequency spin-triplet even-parity (OTE) state and odd-frequency spin-singlet odd-parity (OSO) state. For each of these states, the pairing state in DF is studied. Particular attention is paid to the study of spin-singlet s-wave and spin-triplet p-wave superconductors as the examples of ESE and ETO superconductors. For spin-singlet case the magnitude of the OTE component of the pair amplitude is enhanced with the increase of the exchange field in DF. When the OTE component is dominant at low energy, the resulting LDOS in DF has a zero energy peak (ZEP). On the other hand, in DF / spin-triplet p-wave superconductor junctions LDOS has a ZEP in the absence of the exchange field, where only the OTE paring state exists. With the increase of the exchange field, the ESE component of the pair amplitude induced in DF is enhanced. Then, the resulting LDOS has a ZEP splitting. We demonstrate that the appearance of the dominant OTE component of the pair amplitude is the physical reason of the emergence of the ZEP of LDOS.

9 pages, 9 figures

References in corpus (7)

• A spin triplet supercurrent through the half-metallic ferromagnet CrO2
• Theory of the proximity effect in junctions with unconventional superconductors
• Half-integer Shapiro steps at the 0-pi crossover of a ferromagnetic Josephson junction
• Triplet proximity effect in FSF trilayers
• Anomalous Josephson effect in p-wave dirty junctions
• Odd triplet superconductivity in a superconductor/ferromagnet structure with a spiral magnetic structure
• Long-range odd triplet superconductivity in SF structures with Neel walls

Cited by in corpus (8)

• Odd-frequency pairing in normal metal/superconductor junctions
• Pairing symmetry conversion by spin-active interfaces in superconducting junctions
• Induced Triplet Pairing in clean s-wave Superconductor/Ferromagnet layered structures
• Theory of superconducting and magnetic proximity effect in S$\mid$F structures with inhomogeneous magnetization textures and spin-active interfaces
• The role of interface transparency and spin-dependent scattering in diffusive ferromagnet/superconductor heterostructures
• Theory of Fulde-Ferrell-Larkin-Ovchinnikov state of superconductors with and without inversion symmetry: Hubbard model approach
• Identifying the odd-frequency superconducting state by a field-induced Josephson effect
• Spin-flip scattering and non-ideal interfaces in dirty ferromagnet/superconductor junctions