Coherent magnon-induced domain wall motion in a magnetic insulator channel

Abstract: Advancing the development of spin-wave devices requires high-quality low-damping magnetic materials where magnon spin currents can propagate efficiently and interact effectively with local magnetic textures. We show that magnetic domain walls (DW) can modulate spin-wave transport in perpendicularly magnetized channels of Bi-doped yttrium-iron-garnet (BiYIG). Conversely, we demonstrate that the magnon spin current can drive DW motion in the BiYIG channel device by means of magnon spin-transfer torque. The DW can be reliably moved over 15 um distances at zero applied magnetic field by a magnon spin current excited by an RF pulse as short as 1 ns. The required energy for driving DW motion is orders of magnitude smaller than those reported for metallic systems. These results facilitate low-switching-energy magnonic devices and circuits where magnetic domains can be efficiently reconfigured by magnon spin currents flowing within magnetic channels.