Thermal spin injection and interface insensitivity in permalloy/aluminum metallic non-local spin valves

Abstract

We present measurements of thermal and electrical spin injection in nanoscale metallic non-local spin valve (NLSV) structures. Informed by measurements of the Seebeck coefficient and thermal conductivity of representative films made using a micromachined Si-N thermal isolation platform, we use simple analytical and finite element thermal models to determine limits on the thermal gradient driving thermal spin injection and calculate the spin dependent Seebeck coefficient to be $-0.5\mu \mathrm{V}/\mathrm{K}<S_s<-1.3\mu \mathrm{V}/\mathrm{K}$. This is comparable in terms of the fraction of the absolute Seebeck coefficient to previous results, despite dramatically smaller electrical spin injection signals. Since the small electrical spin signals are likely caused by interfacial effects, we conclude that thermal spin injection is less sensitive to the FM/NM interface, and possibly benefits from a layer of oxidized ferromagnet, which further stimulates interest in thermal spin injection for applications in sensors and pure spin current sources.

References in corpus (13)

• Electrical Detection of Spin Transport in Lateral Ferromagnet-Semiconductor Devices
• Direct Measurement of Room Temperature Non-diffusive Thermal Transport Over Micron Distances in a Silicon Membrane
• The 2014 Magnetism Roadmap
• Antiferromagnonic Spin Transport from Y${}_3$Fe${}_5$O${}_{12}$ into NiO
• Quantitative Temperature Dependence of Longitudinal Spin Seebeck Effect at High Temperatures
• Experimental Verification of Comparability between Spin-Orbit and Spin-Diffusion Lengths
• Control of spin injection by direct current in lateral spin valves
• Spin-dependent Seebeck effect in non-local spin valve devices
• Paramagnetic spin pumping
• Spin Seebeck devices using local on-chip heating
• Verification of the Thomson-Onsager reciprocity relation for spin caloritronics
• Spin Currents injected electrically and thermally from highly spin polarized Co${}_2$MnSi
• Spin transport enhancement by controlling the Ag growth in lateral spin valves

Cited by in corpus (3)

• Thermal effects in spintronic materials and devices: an experimentalist's guide
• Interaction of Magnetization and Heat Dynamics for Pulsed Domain Wall Movement with Joule Heating
• Spincaloritronic signal generation in non-degenerate Si