Electric detection of the spin-Seebeck e ect in magnetic insulator in the presence of interface barrier

摘要

The spin-Seebeck e ect (SSE), the spin-voltage generation as a result of a temperature gradient, has recently been observed in ferrimagnetic insulator LaY_2Fe_5O_(12) 1ms by means of the inverse spin-Hall e ect in Pt 1ms. Here we investigate the SSE using LaY_2Fe_5O_(12)/SiO_2(Cu)/Pt systems, where the LaY_2Fe_5O_(12) and Pt layers are separated by SiC-2 (Cu) thin- lm barriers. The experimental results show that the SSE signal disappears in the LaY_2Fe_5O_(12)/SiO_2/Pt system, but the nite signal appears in the LaY_2Fe_5O_(12)/Cu/Pt system, indicating that the direct contacts between the LaY_2Fe_5O_(12) and normal metals is necessary for generating the SSE signal.