Direct evidence for quantum contact resistance effects in V-groove quantum wires

The effect of quantum contact resistance on one-dimensional (1D) electrical conductance was investigated in quantum wires (QWR) realized with V-shaped GaAs/AlGaAs heterostructure. The transition length between the electron reservoir and the QWR was controlled by employing an electric field. The required transition length is found to decrease with increasing overlap between the 2D states in the reservoir and the 1D states in the QWR.