We request funds to acquire a Quantum Design Superconducting Quantum Interference Device (SQUID) magnetometer to measure the magnetic properties of Mn and Cr-doped Group III- nitride films grown on both doped and undoped AlGaN/GaN heterostructures and single crystalline Mn-based perovskites. Our laboratories are equipped with all the growth, fabrication, testing for electrical and structural capabilities, but this critical piece of equipment is missing. The equipment will be installed in the state of the art Virginia Microelectronic Center research laboratories at VCU. Spurred by room temperature ferromagnetism in GaN:Mn and potential applications combining spin and charge transport for devices under the umbrella of spintronics, we will investigate the fundamental issues in nanoscale semiconducting ferromagnets, such as thermal stability of magnetism, Curie temperature, magnetic viscosity, coercivity, and inter-dot magnetic interactions in GaN quantum dots interfaced with GaMnN/GaCrN films, as well as GaMnN or GaCrN dots interfaced with GaN films. Additionally, we will also investigate magnetism in single crystalline oxides, which are produced in our laboratory using MBE systems and a sputtering system. Specifically, the temperature dependence of magnetization in both field- cooled and zero-field-cooled conditions, magnetization hysteresis and magnetic relaxation related behavior will be measured. These are critical to understand the magnetic behavior of these ferromagnetic semiconductors and magnetic perovskites. Furthermore, magnetic anisotropy and easy axis reorientations related to hole density or epitaxial growth lattice-matching strains will be investigated. The behavior of thin film systems containing a few layers of diluted magnetic materials is complicated by the fact that the absolute magnitude of the magnetic moment is very small, especially at higher temperatures. In order to measure these effects with high precision and obtain the relevant information for fabricating high-quality samples, we need a SQUID magnetometer equipped with sample space oven and sample rotator. The intellectual merit of the proposal is to provide basic and technological understanding of physics of behavior of magnetic spins on spin-based devices from the precise measurement of magnetization properties on dilute magnetic semiconductors and magnetic oxides fabricated using the state-of-the-art techniques. The broader impacts of this proposal are to provide necessary information and feedback on the fabrication of spinotronic devices, search for new magnetic materials for better spin-injection, and understanding of spin degrees of freedom in this new class of ferromagnetic semiconductors.
