Development of in situ Electric field and Electric current capabilities at ISIS

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Small-angle neutron scattering (SANS) is one of the most important techniques for nanostructure determination, being utilized in a wide range of scientific disciplines, such as materials science, physics, chemistry, and biology. This application seeks a studentship to develop the capabilities of applying electric fields or electric currents simultaneously with an applied magnetic field within a cryostat or furnace while studying magnetic skyrmions, topologically protected magnetic textures with promising potential for low energy consumption computing. We propose to demonstrate that the combination of these environmental conditions is vital to fundamental studies of the formation and manipulation of magnetic skyrmions towards the realization of devices. Zoom is a versatile high-intensity SANS instruments equipped with variable temperature and applied magnetic field capabilities, and crucially operates in the angular range (or wavevector range) that we require to observe the very small angle diffraction pattern characteristic of the skyrmion lattice. In order to understand the systems in conditions closer to the working ones, what ISIS is currently lacking and is required by many potential users of Zoom, is an electric field capability. Cu2OSeO3 is seen as attractive material for applications as it is an insulating magnetoelectric whose skyrmion phase stability can be enhanced by applying electric fields. Furthermore, applying an electric field has been shown to nucleate skyrmions from either the competing conical state in bulk crystals or the competing helical state in thin lamellae. For metallic samples such as MnSi and FeGe we will also provide the capability of applying small electrical currents which cause a rotation of the skyrmion diffraction pattern linked to the motion of the skyrmion lattice. This provides a way of measuring the skyrmion velocity in pure and doped materials, a key parameter for future devices. Crucial to the use of providing electric field and current capabilities at ISIS for SANS experiments on Larmor and Zoom, as well as other techniques will be the integration of control software with the environmental management. The PhD student will work on both the hardware and software integration during year 2 of their PhD whilst they are based at ISIS. As part of this PhD project, we also wish to make use of the electric field and current capabilities and apply new methods to a range of existing problems of high interest and impact.