Moving magnetic domain walls with sound alone
Alejandro Rivelles, Rocío Yanes, Luis Torres, Manuel Abuín, Javier Grandal, Maedeh Sepehr, Guzmán Orero-Gámez, Rodrigo Guedas, Laura Fernández-García, Raúl Izquierdo-López, Marco Maicas, Maria del Mar Sanz, Jorge Pedrós, Fernando Calle, Sandra Ruiz-Gómez, Muhammad Waqas Khaliq, Miguel Angel Niño, Saül Vélez, Michael Foerster, Luis López-Díaz, Jose Luis Prieto
Published: 2024/6/18
Abstract
Surface Acoustic Waves (SAW) have been used in spintronic applications to decrease the magnetic field or the electric current required to act on the magnetization. A common belief is that a SAW alone cannot achieve a directed magnetic switching in a device without an assisting magnetic field or electric current. In this work, we demonstrate magnetic domain wall motion driven solely by an acoustic wave. Using XMCD-PEEM, we show extensive evidence of SAW-induced and field-free magnetic domain wall motion (DW) in the direction of the wave propagation. Our micromagnetic simulations reveal a mechanism that allows the SAW to transfer linear momentum to the DW. Experimentally, the largest DW average velocity measured was ~12 m/s, although our simulations predict that velocities in the range of 100 m/s could be attained. This new mechanism opens the door to designing innovative spintronic devices where the magnetization can be controlled exclusively by an acoustic wave.