This Engineering Research Equipment Grant will enable the Department of Electrical Engineering and Computer Science at the Massachusetts Institute of Technology to purchase a superconducting magnet to be dedicated to support research in engineering. The equipment will be used primarily to strengthen on- going research on novel electron waveguide devices. The recent demonstration of electron waveguiding in one-dimensional (1D) semiconductor heterostructures has opened up entirely new possibilities for conceiving advanced electron devices. Much like photons in optical waveguides, in an electron waveguide the modes of electron propagation are determined by the geometry of the confining electrostatic potential. Unlike photons, if a split-gate technology is used, the electron waveguide modes can be easily tuned through the field-effect action of metal gates. In this approach, coupled 1D systems can be synthesized. This represents an entirely novel geometry for electron interaction never before examined. The goal of our research program is the demonstration of electron directional coupling between two closely spaced electron waveguides. Progress to date, under the sponsorship of NSF, include the fabrication of the first balistic dual electron waveguide device and the realization of the first tunneling spectroscopy of an electron waveguide. Detailed magnetic field studies will be instrumental in clarifying the physics of transport and tunneling of electrons in these dual electron waveguide devices.
