Spin-flip scattering and non-ideal interfaces in dirty ferromagnet/superconductor junctions

Abstract

We study the proximity-induced superconducting correlations as well as the local density of states of a ferromagnet, in a ferromagnet/s-wave superconductor heterostructure. We include the effects of spin-flip scattering, non-ideal interfaces, and the presence of impurities in the sample. We employ the quasiclassical theory of superconductivity, solving the Usadel equation with emphasis on obtaining transparent analytical results. As our main result, we report that in a certain parameter regime the spatial oscillations of the anomalous (superconducting) part of the Green's function induced in the ferromagnet by the proximity effect from the s-wave superconductor, are damped out due to the presence of spin-flip processes. As a consequence, spin-flip scattering may under certain conditions actually enhance the local density of states due to the oscillatory behaviour of the latter in ferromagnet/superconductor structures. We also conjecture that the damping could be manifested in the behaviour of the critical temperature ($T_c$) of the s-wave superconductor in contact with the ferromagnet. More specifically, we argue that the non-monotonic decrease of $T_c$ in ferromagnet/s-wave superconductor junctions without magnetic impurities is altered to a monotonic, non-oscillatory decrease when the condition $1>16{\tau }_{\text{sf}}^2{h}^2$ is fulfilled, where ${\tau }_{\text{sf}}$ is the spin-flip relaxation time and $h$ is the exchange field.

11 pages, 5 figures. Accepted for publication in Phys. Rev. B. High-resolution figures to be available in published version

References in corpus (32)

• Proximity effects in superconductor-ferromagnet heterostructures
• Odd Triplet Superconductivity and Related Phenomena in Superconductor-Ferromagnet Structures
• Coupling of two superconductors through a ferromagnet : evidence for a pi-junction
• A spin triplet supercurrent through the half-metallic ferromagnet CrO2
• Long-range effects in superconductor-ferromagnet structures
• Quasiclassical Green's function approach to mesoscopic superconductivity
• Theory of Half Metal-Superconductor Heterostructures
• Odd triplet superconductivity in superconductor/ferromagnet multilayered structures
• Novel Circuit Theory of Andreev Reflection
• Enhancement of the Josephson current by an exchange field in superconductor-ferromagnet structures
• Josephson current in superconductor-ferromagnet structures with a nonhomogeneous magnetization
• Gap Structure of the Spin-Triplet Superconductor Sr2RuO4 Determined from the Field-Orientation Dependence of Specific Heat
• Josephson Effect due to Odd-frequency Pairs in Diffusive Half Metals
• Spontaneous supercurrent induced by ferromagnetic pi-junctions
• Manifestation of the odd-frequency spin-triplet pairing state in diffusive ferromagnet / superconductor junctions
• Density of states and supercurrent in diffusive SNS junctions: role of nonideal interfaces and spin-flip scattering
• Oscillations of Andreev states in clean ferromagnetic films
• Critical current in SFIFS junctions
• Striking properties of Superconductor/Ferromagnet structures with spin-dependent scattering
• Superconducting proximity effect in a diffusive ferromagnet with spin-active interfaces
• Transfer-matrix description of heterostructures involving superconductors and ferromagnets
• Superconducting proximity effect in clean ferromagnetic layers
• Josephson current in a superconductor-ferromagnet junction with two non-collinear magnetic domains
• Local Density of States in Superconductor-Ferromagnetic Hybrid Systems
• Josephson current in a superconductor -- ferromagnet -- superconductor junction with in-plane ferromagnetic domains
• Boundary conditions for quasiclassical equations in the theory of superconductivity
• Interplay between ferromagnetism and superconductivity in tunneling currents
• Tunneling currents in ferromagnetic systems with multiple broken symmetries
• Scattering by magnetic and spin-orbit impurities and the Josephson current in superconductor-ferromagnet-superconductor junctions
• Spin and Charge Josephson effects between non-uniform superconductors with coexisting helimagnetic order
• Conventional Magnetic Superconductors: Coexistence of Singlet Superconductivity and Magnetic Order
• Josephson effect in thin-film superconductor/insulator/superconductor junctions with misaligned in-plane magnetic fields

Cited by in corpus (10)

• Theory of superconducting and magnetic proximity effect in S$\mid$F structures with inhomogeneous magnetization textures and spin-active interfaces
• Josephson current in diffusive multilayer superconductor/ferromagnet/superconductor junctions
• Spin splitting induced in a superconductor by an antiferromagnetic insulator
• The role of interface transparency and spin-dependent scattering in diffusive ferromagnet/superconductor heterostructures
• Thermoelectric properties of a ferromagnet-superconductor hybrid junction: Role of interfacial Rashba spin-orbit interaction
• The influence of anti-chiral edge states on Andreev reflection in graphene-superconductor junction
• Injection of nonequilibrium quasiparticles into Zeeman-split superconductors: a way to create long-range spin imbalance
• Identifying the odd-frequency superconducting state by a field-induced Josephson effect
• Spin-flip Enhanced Thermoelectricity in Superconductor-Ferromagnet Bilayers
• Andreev reflection in a Y-shaped graphene-superconductor device