Introduction to stellarators*

Stellarators, characterised by their three-dimensionally shaped toroidal magnetic fields, represent a broad magnetic confinement fusion concept. While offering vast possibilities and potential advantages over other fusion concepts, stellarators require careful curation to attain desired properties. Recent experimental evidence showcasing the attainment of excellent neoclassical confinement, a historical challenge for stellarators, through theoretical design has reignited interest in this concept. Consequently, stellarators emerge as both a captivating subject of theoretical investigation and a significant practical contender for achieving fusion.

This introductory talk aims to motivate and elucidate some of the key stellarator concepts, emphasizing key elements essential to their study and design. The presentation will set the ground for the remaining of the mini-conference, touching upon key aspects such as particle and neoclassical confinement, MHD equilibrium, or the reduction of plasma current requirements.