The skyrmion switch: turning magnetic skyrmion bubbles on and off with an electric field

International audienceNanoscale magnetic skyrmions are considered as potential information carriers for future spintronics memory and logic devices. Such applications will require the control of their local creation and annihilation, which involves so far solutions that are either energy consuming or difficult to integrate. Here we demonstrate the control of skyrmion bubbles nucleation and annihilation using electric field gating, an easily integrable and potentially energetically efficient solution. We present a detailed stability diagram of the skyrmion bubbles in a Pt/Co/oxide trilayer and show that their stability can be controlled via an applied electric field. An analytical bubble model, with the Dzyaloshinskii-Moriya interaction imbedded in the domain wall energy, account for the observed electrical skyrmion switching effect. This allows us to unveil the origin of the electrical control of skyrmions stability and to show that both magnetic dipolar interaction and the Dzyaloshinskii-Moriya interaction play an important role in the skyrmion bubble stabilization. Magnetic skyrmions are swirling spin textures with nanoscale dimensions and a non-trivial topology. They were studied theoretically more than two decades ago and observed at low temperature in the form of hexagonal lattices in non-centrosymmetric crystals and magnetic multilayers. Recently several groups have reported the observation of magnetic skyrmions at room temperature (RT) in conventional transition-metal-based magnetic multilayers. In some systems, the skyrmions present relatively large dimensions (~1 μm) and are called 'skyrmion bubbles'. While classical bubbles ar