Impact of Dzyaloshinskii-Moriya interactions on the thermal stability factor of heavy metal/magnetic metal/oxide based nano-pillars

Abstract

We studied the thermal stability of ultrathin perpendicular magnetized nanodots in the presence of the Dzyaloshinskii-Moriya interaction (DMI) using a Minimum Energy Path (MEP) method. We find that the smallest energy barrier is associated with the energy path based on domain wall nucleation and propagation down to 25 nm lateral size. We show that the DMI has a detrimental impact on the thermal stability factor of square Pt/Co/AlOx dots, which decreases linearly with the DMI amplitude. Our study reveals that the DMI limits the downscaling of MRAM cells based on heavy metal (HM)/ferromagnet (FM)/oxide trilayers.

A comparison of two different mechanisms for deterministic spin orbit torque magnetization switching

“…In the presence of interfacial DMI the energy barrier corresponding to a DW nucleation will be reduced by a factor −πDS 37 where D is the DMI constant. This is in agreement with some numerical calculations showing that DMI actually reduces the energy barrier for switching in magnetic nanoelements 38,39 .…”

Surface Roughness Influence on Néel-, Crosstie, and Bloch-Type Charged Zigzag Magnetic Domain Walls in Nanostructured Fe Films

“…So, the study of magnetic domain structures is important, and they are continuously the object of analysis and research [ 19 , 20 , 21 , 22 , 23 ]. Indeed, the control of magnetic domain walls in differently shaped materials such as thin films [ 24 ], nanoparticles [ 25 ], nanowires [ 26 ], nanodots [ 27 ], etc., is the subject of numerous investigations for the development of functional materials for scientific and technological applications.…”

Entropy-reduced Retention Times in Magnetic Memory Elements: A Case of the Meyer-Neldel Compensation Rule

“…In Fig. 1d, we show the internal energy barrier as a function of D. As one can expect, the energy of the wall varies linearly with D [23,24,30]. We then set D = 0.25 mJ/m 2 and vary K from 0.1 to 0.26 MJ/m 3 .…”

“…The typical configuration at the saddle point (SP) for the switching of the magnetization in such systems is two oppositely magnetized domains separated by a domain wall [23]. The DMI selects a preferred chirality of the wall and lowers its energy, thus leading to lower activation energies and, from the assumption f 0 ∼ 1 GHz, dramatically reduced retention times [23,24].…”