Observation of magnetic skyrmions in unpatterned symmetric multilayers at room temperature and zero magnetic field

Abstract

Magnetic skyrmions are promising candidates for the next generation of spintronic devices due to their small size and topologically protected structure. One challenge for using these magnetic states in applications lies on controlling the nucleation process and stabilization that usually requires an external force. Here, we report on the evidence of skyrmions in unpatterned symmetric Pd/Co/Pd multilayers at room temperature without prior application of neither electric current nor magnetic field. By decreasing the ferromagnetic interlayer thickness, the tuning of the physical properties across the ferromagnetic/non-magnetic interface gives rise to a transition from worm like domains patterns to isolated skyrmions as demonstrated by magnetic force microscopy. On the direct comparison of the measured and simulated skyrmions size, the quantitative interfacial Dzyaloshinskii-Moriya interaction (iDMI) was estimated, reveling that isolated skyrmions are just stabilized at zero magnetic field for low values of iDMI. Our findings provide new insights towards the use of stabilized skyrmions for room temperature devices in nominally symmetric multilayers.

arXiv comment14 pages and 4 figures

References in corpus (13)

• The design and verification of Mumax3
• Advances in the Physics of Magnetic Skyrmions and Perspective for Technology
• Additive interfacial chiral interaction in multilayers for stabilization of small individual skyrmion at room temperature
• Skyrmions at room temperature : From magnetic thin films to magnetic multilayers
• Dynamics of Dzyaloshinskii domain walls in ultrathin magnetic films
• Room temperature chiral magnetic skyrmion in ultrathin magnetic nanostructures
• Anatomy of Dzyaloshinskii-Moriya Interaction at Co/Pt Interfaces
• Field-Dependent Size and Shape of Single Magnetic Skyrmions
• Room-temperature current-induced generation and motion of sub-100nm skyrmions
• Current-induced skyrmion generation and dynamics in symmetric bilayers
• Thickness dependence of the interfacial Dzyaloshinskii-Moriya interaction in inversion symmetry broken systems
• Observation of stable Neel skyrmions in Co/Pd multilayers with Lorentz transmission electron microscopy
• Chirality in magnetic multilayers probed by the symmetry and the amplitude of dichroism in X-ray resonant magnetic scattering