Observation of the Dzyaloshinskii–Moriya interaction via asymmetry in magnetization reversal

Abstract

Due to its importance in future spintronic-based memory devices, the Dzyaloshinskii–Moriya interaction (DMI) has been under intense investigation recently. Yet the feasibility of developing straightforward DMI measurement methods, especially using quasi-static tools, is debatable. Here, we present the observation of a shifted, asymmetric magnetization reversal manifested by interfacial DMI (iDMI) via magnetoresistance (MR) measurements for the first time. A shifted asymmetric MR response results from iDMI in an ultrathin symmetric unpatterned [Ni80Fe20/Pt] ×10 multilayer stack. Moreover, to reveal the presence of iDMI, we have experimentally seen iDMI from nonreciprocity in spin-wave dispersion using Brillouin light-scattering. Also, as a previously developed quasi-static method, we compare the MR results with the magneto-optical Kerr effect with the observed MR results. Our findings open pathways towards direct observation of iDMI in magnetic multilayers.

Nonzero Spontaneous Magnetic Moment along the b-Axis and the 2-Fold Spin Reorientation Transition in a Er0.4Gd0.6FeO3 Single Crystal

“…Rare-earth orthoferrites (RFeO 3 ) have a distorted perovskite structure with a space group of Pbnm . − As a functional material family, RFeO 3 attracts great scientific interest and has technological significance for potential applications such as magneto-optical switch, ultrafast optomagnetic recording, precession excitation induced by terahertz pulses, and magnetism-induced ferroelectric multiferroics. − Their abundant magnetic properties mainly originate from 3d-electrons of Fe 3+ and 4f-electrons of R 3+ . , The two magnetic ions (R 3+ and Fe 3+ ) form in three types of magnetic sublattices, including Fe 3+ –Fe 3+ , Fe 3+ –R 3+ , and R 3+ –R 3+ sublattices . The strongest one of those is Fe 3+ –Fe 3+ with G-type antiferromagnetic interaction, which causes the iron ions to orient opposite to all nearest neighbors in three dimensions below the first Neel temperature at 650–700 K. The presence of a Dzyaloshinskii–Moriya interaction − induces an asymmetric electronic exchange, resulting in a spontaneous magnetization in the c -axis of a RFeO 3 single crystal below the Neel temperature. In RFeO 3 , three well-documented spin configurations are Γ 1 (A x , G y , G z ), Γ 2 (F x , C x , G x ), and Γ 4 (G x , A y , F z ), and the mutual conversion between two different configurations is known as spin reorientation transition (SRT). − It is worth noting that the origin of SRT is distinct for different RFeO 3 , and we generally pay attention to temperature-induced SRT.…”

Skyrmion dynamics induced by surface acoustic waves in antiferromagnetic systems

“…Skyrmions, being a topologically protected soliton, could be stabilized as a nanosize whirling spin texture in noncentrosymmetric magnetic materials [24][25][26]. The core reason for stabilization at the nanoscale is the inhomogeneous DMI in inversion asymmetric magnetic materials [27][28][29][30][31][32][33]. Isolated skyrmion creation and dynamics have been reported as a metastable state in both FM and AFM systems [34][35][36][37][38][39].…”