Application of microwave techniques in the analysis of quantum waveguide structures and devices

An extension of the generalized scattering matrix (GSM) technique is formulated to compute the GSM of nonuniform quantum waveguide structures with two-dimensional quantum confinement of electronic states. Low-temperature I-V characteristics for a double constriction are presented, exhibiting a region of negative differential resistance (NDR). A simple design procedure for increasing the temperature range with achievable NDR is introduced.<>