Fig. 1: Experimental system.
From: Evidence for spin current driven Bose-Einstein condensation of magnons
a Schematics of the experiment. Magnon gas in a BiYIG film with PMA is driven by the injection of the spin current Is created by SHE in the Pt electrode with an active area of 1 × 2 μm2. The spectral distribution of magnons is measured by analyzing the light inelastically scattered from magnons. Transparent sGGG substrate is not shown for clarity. b Normalized BLS spectrum of magnons in the BiYIG film measured at I = 0 and µ0H0 = 100 mT. c Calculated dispersion spectrum of magnons in the BiYIG film. Solid curves correspond to magnons with the wavevector k oriented parallel to H0. Dashed curves correspond to magnons with the wavevector k oriented perpendicular to H0. fFMR marks the frequency of the ferromagnetic resonance. fmin marks the frequency of the lowest-energy magnon state. Insets schematically show the distributions of the dynamic magnetization across the film thickness for the fundamental and the PSW magnon mode.
