Thermal generation of spin current in epitaxial CoFe2O4 thin films

Abstract

The longitudinal spin Seebeck effect (LSSE) has been investigated in high-quality epitaxial CoFe2O4 (CFO) thin films. The thermally excited spin currents in the CFO films are electrically detected in adjacent Pt layers due to the inverse spin Hall effect (ISHE). The LSSE signal exhibits a linear increase with increasing temperature gradient, yielding a LSSE coefficient of ~100 nV/K at room temperature. The temperature dependence of the LSSE is investigated from room temperature down to 30 K, showing a significant reduction at low temperatures, revealing that the total amount of thermally generated magnons decreases. Furthermore, we demonstrate that the spin Seebeck effect is an effective tool to study the magnetic anisotropy induced by epitaxial strain, especially in ultrathin films with low magnetic moments.

17 pages, 4 figures

References in corpus (8)

• Spin Seebeck insulator
• Observation of the Spin-Seebeck Effect in a Ferromagnetic Semiconductor
• Theory of magnon-driven spin Seebeck effect
• Critical suppression of spin Seebeck effect by magnetic fields
• The effect of the magnon dispersion on the longitudinal spin Seebeck effect in yttrium iron garnets (YIG)
• Spin Seebeck effect in antiferromagnets and compensated ferrimagnets
• Spin-Hall magnetoresistance and spin Seebeck effect in spin-spiral and paramagnetic phases of multiferroic CoCr2O4 films
• Magnetic field control of the spin Seebeck effect

Cited by in corpus (11)

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• Absence of magnetic proximity effects in magnetoresistive Pt/CoFe2O4 hybrid interfaces
• Enhanced magnon spin transport in NiFe${}_2$O${}_4$ thin films on a lattice-matched substrate
• Static Magnetic Proximity Effect in Pt Layers on Sputter-Deposited NiFe2O4 and on Fe of Various Thicknesses Investigated by XRMR
• Exploiting Coherence in Nonlinear Spin-Superfluid Transport
• Tunable Ferromagnetism in LaCoO3 Epitaxial Thin Films
• Magnetic domain wall pinning in cobalt ferrite microstructures
• Anisotropic Band-Split Magnetism in Magnetostrictive CoFe${}_2$O${}_4$