Strain-mediated Symmetry Broking Switch with Perpendicular Magnetic Anisotropy

Magnetic switch with perpendicular magnetic anisotropy (PMA) is a promising method for controlling magnetization in several applications like magnetic tunnel junction and magnetic memory. However, incoherence happens during the switch process and lower the switch frequency of the magnetic bits. Symmetry broking can help solve this problem. Here, we present a field-free method for the symmetry broking and then increase the switch speed of the magnetization. A strain-mediated method with geometric asymmetry is presented here. In this work, we build a finite element model that consists a 50 nanometer diameter nanodisk with a varied thickness on the top of a 50 nanometer thick PZT (Pby[ZrxTi1-x]O3) thin film. The results show a 66% faster switch than symmetry PMA switching (0.85 nanosecond to 0.29 nanosecond) under same energy consumption. Finally, we explore the mechanism of the symmetry broking of varying thickness nanodot with calculating the energy profile.