9313726 Chandrasekhar This is an experimental research program focused on low temperature electron transport in nanofabricated systems in which strong electrostatic interactions between electrons lead to Coulomb blockade and single electron charging phenomena. The experiments are designed to increase fundamental understanding of the microscopic mechanism of electron transport in this regime, with emphasis on modifications introduced by quantum effects. The structures consist of short insulating wires placed between metallic contact electrodes. The goal is to understand the origin of the single electron charging effects that have been observed in this novel system. With an eye to potential device applications, different methods of increasing the temperature range over which the Coulomb blockade effects can be observed will be investigated by exploiting some unique properties of insulators. The project involves graduate students in research that is at the cutting edge of nanolithographic fabrication techniques. %%% This experimental project deals with the motion of individual electrons among ultrasmall structures that are fabricated by tracing patterns only a few atoms in width using a finely focused electron beam. The resulting structures show remarkable responses at low temperatures to applied electric and magnetic fields. The response arises from quantum effects that are only poorly understood in the structures under study. The ability of detection motion of a single electron has fundamental interest and is technologically significant as a route to the smallest microelectronics device currently envisioned. The project will employ insulating nanostructures which have potential for allowing operation of the microdevices at higher temperatures. ***
