Driving skyrmions with low threshold current density in Pt/CoFeB thin film

TL;DR

This paper demonstrates low-threshold current density for skyrmion motion in Pt/CoFeB/MgO heterostructures, highlighting their potential for energy-efficient spintronic devices at room temperature.

Contribution

The study reports the stabilization of skyrmions at room temperature in Pt/CoFeB/MgO and shows their low current-driven mobility, indicating a low pinning landscape and energy-efficient control.

Findings

Skyrmions are stabilized at room temperature in the heterostructure.

Low threshold current density enables skyrmion motion at few 10 m/s.

Presence of low pinning landscape facilitates easy skyrmion manipulation.

Abstract

Magnetic skyrmions are topologically stable spin swirling particle like entities which are appealing for next generation spintronic devices. The expected low critical current density for the motion of skyrmions makes them potential candidates for future energy efficient electronic devices. Several heavy metal/ferromagnetic (HM/FM) systems have been explored in the past decade to achieve faster skyrmion velocity at low current densities. In this context, we have studied Pt/CoFeB/MgO heterostructures in which skyrmions have been stabilized at room temperature (RT). It has been observed that the shape of the skyrmions are perturbed even by the small stray field arising from low moment magnetic tips while performing the magnetic force microscopy (MFM), indicating presence of low pinning landscape in the samples. This hypothesis is indeed confirmed by the low threshold current density to drive the skyrmions in our sample, at velocities of few 10m/s.