Physics

Electron

Spin Hall effect

Magnetization

Ferrimagnetism

Skyrmion

Magnetic field

Hall effect

Spin polarization

Condensed matter physics

Spin (aerodynamics)

Quantum mechanics

Thermal Hall effect

Thermodynamics

Nature Nanotechnology

In the presence of a magnetic field, the flow of charged particles in a conductor is deflected from the direction of the applied force, which gives rise to the ordinary Hall effect. Analogously, moving skyrmions with non-zero topological charges and finite fictitious magnetic fields exhibit the skyrmion Hall effect, which is detrimental for applications such as skyrmion racetrack memory. It was predicted that the skyrmion Hall effect vanishes for antiferromagnetic skyrmions because their fictitious magnetic field, proportional to net spin density, is zero. Here we investigate the current-driven transverse elongation of pinned ferrimagnetic bubbles. We estimate the skyrmion Hall effect from the angle between the current and the bubble elongation directions. The angle and, hence, the skyrmion Hall effect vanishes at the angular momentum compensation temperature where the net spin density vanishes. Furthermore, our study establishes a direct connection between the fictitious magnetic field and the spin density. The temperature-dependent transverse elongation of ferrimagnetic bubbles provides experimental evidence for an evanescent skyrmion Hall effect at zero spin density.

Vanishing skyrmion Hall effect at the angular momentum compensation temperature of a ferrimagnet