Speaker: Roberto Myers (Ohio State University)
The extreme energy landscapes for electrons and magnetic ions that exist in GaN-based materials offer a pathway for room temperature semiconductor spintronics and investigation of spins in polarization engineered and strongly confined systems. We are using molecular beam epitaxy to explore carrier-mediated magnetism in confined electronic structures consisting of two-dimensional electron (2DEG) or hole gases doped with rare-earth (Gd) magnetic moments. Magnetic semiconductors exhibit electric field control of magnetism and can be used as a source of thermally induced spin currents through the recently discovered spin-Seebeck effect. Using polarization doping we examine effects of Fermi level position on magnetism and magneto-transport. A related project aims to develop room temperature spin injection, transport, and detection in GaN 2DEGs. Such structures also allow for charge modulation at high speeds. Lastly, we discuss self-assembled nanowires for three-dimensional design of heterostructures. These materials will be used to study carrier-mediated ferromagnetism, and spin transport in low-dimensional, single crystal environments.