Imaging Spin Injection and Accumulation in Semiconductors. Information that is stored on your computer hard drive is encoded in the spin of electrons. One of the research projects in IRG3 is devoted to understanding the transport of spin-polarized electrons from metals (like the materials used in a hard drive) directly into semiconductors, which are the materials used in the processing components of a computer. The next step in this process is understanding what happens to electron spins as they move around inside the semiconductor. A prototypical spin transport device consists of two iron electrodes, which function as "source" and "detector," at opposite ends of a semiconductor channel. IRG3 graduate student Xiaohua Lou and postdoc Christoph Adelmann, working with Professors Paul Crowell and Chris Palmstrøm have fabricated these types of devices. Collaborators from Los Alamos National Laboratory have imaged the flow of spin-polarized electrons, showing how they emerge from the ferromagnetic source and diffuse in the semiconductor. Furthermore, this work shows how spin-polarized electrons "accumulate" at the ferromagnetic detector. Building on previous work in IRG3, this experiment also demonstrated how a ferromagnetic electrode can be used as a detector of spin-polarized electrons in the semiconductor. [S. A. Crooker, M. Furis, X. Lou, C. Adelmann, D. L. Smith, C. J. Palmstrøm, and P. A. Crowell, "Imaging Spin injection and Accumulation in Lateral Ferromagnet-semiconductor Structures,"Science 309, 2191(2005).]