The objective of this research is the development and characterization of new silicon devices that should exhibit a variety of magnetic behaviors at will - even though consisting of non-magnetic silicon. Recent theoretical results demonstrated that on a finely-patterned two-dimensional lattice, electrons are confined to intersection sites; at higher concentrations, additional electrons also occupy interstitial sites. Many-body quantum theory predicts that at these differing concentrations, Ferromagnetic, Antiferromagnetic, and several Other Phases will arise, triggered by electron-electron interactions. It should be possible to "switch" between these thermodynamically stable phases merely by changing a control voltage. Such controllable "Spin Lattices" should prove useful in spintronic devices. The approach is to etch lattices into the gate electrodes of silicon metal-oxide-semiconductor transistors. Theoretical and numerical efforts will evaluate their novel electrical and magnetic properties. Importantly, the phenomena should scale up to room temperature as lattice features scale down below 10 nm.
A broader intellectual contribution of this project is the connection of the most basic quantum physics with advanced silicon microelectronics. Successful devices may play an important economic role by replacing transistors when further transistor miniaturization according to "Moore's Law" becomes impractical, potentially finding uses in spintronics, quantum computation, and other applications one can only conjecture at present. This project will train graduate and undergraduate students in scientific and engineering research, with undergraduate students preparing samples and investigating transistors properties for spin lattices. Graduate students will broadly disseminate this knowledge by creating an interactive exhibit in the new "Utah Museum of Science and Technology".
