Grant: Research Tools and Instruments - Category 1 (<$150,000)

The "spin" of an electron--a physical characteristic that is analogous to but independent of its charge--has gained widespread recent attention due to the potential applications of spintronics for quantum or classical information processing. Spintronics is so-named in analogy to electronics, but where information is stored and transmitted in the spin of an electron rather than its charge. Spintronic circuits have the potential for extreme increases in computer processing speed and for reducing the power necessary to run the computer. Our group studies the behavior of electron spins in a variety of materials, and already we have had substantial success in our research, with three papers from the past year published in some of the most prestigious journals in physics. A unifying characteristic of the systems we study is that they are effectively two-dimensional. We make spin measurements in conventional semiconductor materials, like the 2D conducting layer of GaAs found in a cell-phone transistor, and in novel materials like graphene--a single atomic layer of carbon atoms, the two-dimensional building block of graphite. The most effective external parameter for gaining control over electron spins in an experiment is magnetic field. But most magnetic fields affect both the charge and the spin of an electron, so it is often difficult to disentangle which field effects are associated with spin. Magnetic fields that are perfectly aligned with the 2D samples we measure do not create the confusion mentioned above, because they affect only the spin. This proposal is for a magnet that allows independent control of the magnetic field direction, in order to achieve this level of perfect alignment. It will enable us to build on the success we have achieved so far, investigating new types of spin behaviors in electronic circuits, and pushing forward the march to successful spintronics.