Applying heat to a magnetoelectric antiferromagnet enables an electric field control of magnon spin currents.

The effect of the Dzyaloshinskii–Moriya (DM) interaction on the vortex in magnetic microdisk was investigated by micro-magnetic simulation based on the Landau–Lifshitz–Gilbert equation. Our results show that the DM interaction modifies the size of the vortex core, and also induces an out-of-plane magnetization component at the edge and inside the disk. The DM interaction can destabilizes one vortex handedness, generate a bias field to the vortex core and couple the vortex polarity and chirality. This DM-interaction-induced coupling can therefore provide a new way to control vortex polarity and chirality.

Electric current sensors are widely utilized in high-frequency power and electronic circuits which spread over numerous industries. Here, a current sensor based on the high-Q whispering gallery mode optical capillary microresonator filled with Terfenol-D nanoparticles is experimentally demonstrated. The device shows a peak AC current sensitivity of 5.285 μA Hz ^-1/2 with a corresponding high accuracy of 0.0009%. It possesses a wide detection frequency bandwidth of approximately 12 MHz and exhibits good linearity, enabling for partial discharge signals detection.

We measured spin Seebeck signals at the top and bottom surfaces of an antiferromagnetic ${\mathrm{Cr}}_2{\mathrm{O}}_3$ film, using a $\mathrm{Pt}/{\mathrm{Cr}}_2{\mathrm{O}}_3/\mathrm{Pt}$ trilayer. Our experimental data, combined with micromagnetic simulations, clearly demonstrate that the uncompensated sublattice at the top and bottom surfaces plays a decisive role in determining the symmetry of the spin Seebeck signals, providing fundamental insight for understanding the generation of spin Seebeck signal in antiferromagnetic materials.

The effect of the Dzyaloshinskii–Moriya interaction (DMI) on magnetic vortex gyration is investigated systematically through micromagnetic simulations. Our results show that the DMI can lift the degeneracy of vortex gyration eigenfrequencies for vortices with left- and right-handedness. For vortex gyration excited by an in-plane AC resonant field, the DMI can strongly influence the gyration amplitude and the critical field for core switching, depending on the sign of the DMI and the vortex handedness. The DMI-induced edge state has a strong effect on the vortex core gyration as the core approaches the disk edge.

Magnetic vortices are characterized by the senses of in-plane magnetization chirality and by the polarity of the vortex core. The electrical control of vortex polarity and chirality is highly demanded not only for fundamental understanding of spin dynamics in nanodisks under different circumstances, but also for technological applications, such as magnetic nonvolatile memories and spin torque oscillators for neuromorphic computing. We report an alternative approach that enables one to electrically control both the vortex chirality and polarity with low energy consumption. Thorough micromagnetic simulations, we show that in thin nanodisks of diameters larger than 160 nm, with the presence of a current-induced Oersted field, the dynamic transformation of the edge solitons is able to efficiently switch both vortex chirality and polarity with low current under certain circumstances. We then develop an approach to directly write any of the four vortex states by electrical current pulses from a random state. We further investigate the switching phase diagram as a function of disk diameters. The results show that the switching process is highly size dependent. As the disk diameter becomes smaller than 160 nm, the switch of vortex core (VC) chirality and polarity always take place at the same time, resulting in an unchanged handedness before and after switching. Furthermore, the critical switch current can be as low as $3\times {10}^6\text{A/c}{\text{m}}^2$, indicating a possible way for low current switch of vortex chirality in small disks.