Direct measurement of magnon temperature by magneto-optic Kerr effect in YIG

Magnon-phonon thermal relaxation holds a fundamental role in condensed matter physics, and the difference between local phonon and magnon temperature Delta T ( mp ) as an important part of this subfield was theoretically considered responsible for the spin Seebeck effect. Experimental determination of Delta T ( mp ) is necessary to give more insight into the magnon-phonon coupling. Here we report spatially resolved measurements of magnon temperature performed by magneto-optic Kerr effect in yttrium iron garnet. Our results indicate a strong interaction between magnon and phonon subsystems in YIG with an upper limit of the phonon-magnon thermal relaxation length of 1.4 mm, and means this method is valid.

Automated summary

The study conducted spatially resolved measurements of magnon temperature in yttrium iron garnet using the magneto-optic Kerr effect. The results indicate a strong interaction between magnon and phonon subsystems in YIG, with an upper limit of the phonon-magnon thermal relaxation length of 1.4 mm, validating the effectiveness of this method.