Spin currents injected electrically and thermally from highly spin polarized Co2MnSi

• Published in: Applied physics letters Vol. 107; no. 8
• Main Authors: Pfeiffer, Alexander, Hu, Shaojie, Reeve, Robert M., Kronenberg, Alexander, Jourdan, Martin, Kimura, Takashi, Kläui, Mathias
• Format: Journal Article
• Language: English
• Published: 24-08-2015
• ISSN: 0003-6951; 1077-3118
• DOI: 10.1063/1.4929423

We demonstrate the injection and detection of electrically and thermally generated spin currents probed in Co2MnSi/Cu lateral spin valves. Devices with different electrode separations are patterned to measure the non-local signal as a function of the electrode spacing and we determine a relatively high effective spin polarization α of Co2MnSi to be 0.63 and the spin diffusion length of Cu to be 500 nm at room temperature. The electrically generated non-local signal is measured as a function of temperature and a maximum signal is observed for a temperature of 80 K. The thermally generated non-local signal is measured as a function of current density and temperature in a second harmonic measurement detection scheme. We find different temperature dependences for the electrically and thermally generated non-local signals, which allows us to conclude that the temperature dependence of the signals is not just dominated by the transport in the Cu wire, but there is a crucial contribution from the different generation mechanisms, which has been largely disregarded till date.