Superconducting spin-valve effect in heterostructures with ferromagnetic Heusler alloy layers

Abstract

We report a comparative analysis and theoretical description of the superconducting properties of two spin-valve-valve structures containing the Heusler alloy Co${}_2$Cr${}_{1-x}$Fe${}_x$Al${}_y$ as one of two ferromagnetic (F1 or F2) layers of the F1/F2/S structure, where S stands for the superconducting Pb layer. In our experiments we used the Heusler alloy layer in two roles: as a weak ferromagnet on the place of the F2 layer and as a half-metal on the place of the F1 layer. In the first case, we obtained a large ordinary superconducting spin-valve effect $\Delta T_c$ assisted by the triplet superconducting spin-valve effect $\Delta T_c^{trip}$. In the second case, we observed a giant magnitude of $\Delta T_c^{trip}$ reaching 0.5 K. An underlying theory based on the solution of the Usadel equations using Kupriyanov-Lukichev boundary conditions with arbitrary material parameters for all layers and arbitrary boundary parameters for all interfaces is presented in Appendix. We find a good agreement between our experimental data and theoretical results.

arXiv comment13 pages, 7 figures

References in corpus (25)

• Odd Triplet Superconductivity and Related Phenomena in Superconductor-Ferromagnet Structures
• Coupling of two superconductors through a ferromagnet : evidence for a pi-junction
• Superconducting Spintronics
• Quiet SDS Josephson Junctions for Quantum Computing
• Nonmonotonic critical temperature in superconductor/ferromagnet bilayers
• Evidence for Triplet Superconductivity in a Superconductor-Ferromagnet Spin Valve
• Superconducting triplet spin valve
• Observation of the Triplet Spin-Valve Effect in a Superconductor-Ferromagnet Heterostructure
• Full spin switch effect for the superconducting current in a superconductor/ferromagnet thin film heterostructure
• Angular Dependence of the Superconducting Transition Temperature in Ferromagnet-Superconductor-Ferromagnet Trilayers
• Manifestation of New Interference Effects in Superconductor/Ferromagnet Spin Valve
• Controlled suppression of superconductivity by the generation of polarized Cooper pairs in spin valve structures
• Half-Metallic Superconducting Triplet Spin Valve
• Angular dependence of superconductivity in superconductor / spin valve heterostructures
• Triplet proximity effect in superconducting heterostructures with a half-metallic layer
• Minigap in superconductor-ferromagnet junctions with inhomogeneous magnetization
• Magnetization-control and transfer of spin-polarized Cooper pairs into a half-metal manganite
• Half-Metallic Superconducting Triplet Spin MultiValves
• Proximity effects and triplet correlations in Ferromagnet/Ferromagnet/Superconductor nanostructures
• Isolation of proximity-induced triplet pairing channel in a superconductor/ferromagnet spin valve
• Boosting the superconducting spin valve effect in a metallic superconductor/ferromagnet heterostructure
• Superconducting spin valves controlled by spiral re-orientation in B20-family magnets
• Superconducting switching due to triplet component in the Pb/Cu/Ni/Cu/Co${}_2$Cr${}_{1-x}$Fe${}_x$Al${}_y$ spin-valve structure
• Critical temperature of superconductor/ferromagnet bilayers
• Transport in Ferromagnet/Superconductor spin valves

Cited by in corpus (9)

• Critical supercurrent and ${\varphi }_0$ state for probing a persistent spin helix
• Superconducting spin valve effect in the Co/Pb/Co heterostructure with insulating interlayers
• Superconducting spin valves based on antiferromagnet/superconductor/antiferromagnet heterostructures
• Expanding the operational temperature window of a superconducting spin valve
• Neel proximity effect in superconductor/antiferromagnet heterostructures
• Superconducting spin valve effect in Fe/Si${}_3$N${}_4$/Pb/Si${}_3$N${}_4$/Fe heterostructures
• Inverse proximity effect in thin-film superconductor/magnet heterostructures with metallic and insulating magnets
• Density of states in the heterostructure ferromagnetic insulator-superconductor-ferromagnetic insulator
• Triplet correlations in superconductor/antiferromagnet heterostructures: dependence on type of antiferromagnetic ordering