Optimizing Quasi-Poloidal Stellarators

Stellarators offer several distinct advantages over tokamaks as magnetic-confinement fusion devices. Recent progress has been made in optimizing stellarators for quasi-axisymmetry (QA) and quasi-helical (QH) symmetry. However, quasi-poloidal (QP) stellarators have not been studied as thoroughly as QH or QA designs. QP symmetry indicates that the contours of magnetic field strength close poloidally, resulting in a variety of benefits: QP design promises steady-state operation with reduced bootstrap current, reduced orbit width, and increased E x B shear. This project utilizes the optimization software simsopt to find novel QP stellarator configurations. Additionally, we study the tradeoffs of QP symmetry with geometric constraints such as the aspect, elongation, and mirror ratio.