Temperature dependence of the non-local spin Seebeck effect in YIG/Pt nanostructures

• Main Authors: Kathrin Ganzhorn, Tobias Wimmer, Joel Cramer, Richard Schlitz, Stephan Geprägs, Gerhard Jakob, Rudolf Gross, Hans Huebl, Mathias Kläui, Sebastian T. B. Goennenwein
• Format: Article
• Language: English
• Published: AIP Publishing LLC 2017-08-01
• Series: AIP Advances
• Online Access: http://dx.doi.org/10.1063/1.4986848

We study the transport of thermally excited non-equilibrium magnons through the ferrimagnetic insulator YIG using two electrically isolated Pt strips as injector and detector. The diffusing magnons induce a non-local inverse spin Hall voltage in the detector corresponding to the so-called non-local spin Seebeck effect (SSE). We measure the non-local SSE as a function of temperature and strip separation. In experiments at room temperature we observe a sign change of the non-local SSE voltage at a characteristic strip separation d0, in agreement with previous investigations. At lower temperatures however, we find a strong temperature dependence of d0. This suggests that both the angular momentum transfer across the YIG/Pt interface as well as the transport mechanism of the magnons in YIG as a function of temperature must be taken into account to describe the non-local SSE.