We propose an experimental investigation on the fabrication and characterization of nanometer-scale structures exhibiting quantum interference effects in gallium arsenide semiconductor materials with applications to novel quantum effect devices. The primary objective of the proposed research is to demonstrate transistor action by quantum modulation in nanostructures. Specifically, we propose to fabricate and characterize a three terminal, T-shaped device called the Quantum Modulated Transistor (QMT) as a vehicle to investigate the feasibility of realizing transistor action based on confinement-induced quantum effects. The quasi-one-dimensional electron channel for the QMT will be fabricated using electron beam lithography and chemically assisted ion beam etching techniques in A1GaAs/GaAs modulation-doped field effect transistor (MODFET) heterostructures. Molecular- beam-epitaxy grown planar-doped, single and double heterostructure MODFET materials exhibiting enhanced mobility and electron sheet density will be used. The QMT will be exhaustively characterized through current-voltage measurements at various temperatures down to 1 K. A successful realization of high confinement nanostructures and the QMT should lead to the observation of novel quantum effects and provide a new class of ultra-small devices for performing complex electronic functions.
