This DMREF project aims to make breakthroughs in understanding and designing novel superconductors, magnetic semiconductors, and other magnetic materials. The research can lead to development of materials with higher transition temperatures suitable for applications to electronic devices with novel functionalities. To achieve this goal, the team members will unite their forces and expertise to characterize high-quality specimens with multiple experimental probes, to explore electric field-effect doping of charge carriers using nano-scale devices, to interpret the results using advanced computational models, and to design and synthesize new materials. As demonstrated in recent discoveries of ferromagnetic semiconductors that have crystal structures identical to those of Fe-based high-Tc superconductors, encounters and coherent collaboration between experts from different research communities will lead to unanticipated breakthroughs. This project will provide a unique collaborative experience involving leading researchers, graduate students, and postdocs with multiple research fields and techniques that will make important contributions to the development of the future leaders of modern physics research.