Quantum-mechanical features in the resistance of a submircon junction

Many features found in the resistance of a junction between quasi-one-dimensional wires have been recently attributed to classical ballistic effects. Using experiments and calculations, we show that at low temperature, electron confinement and coherent scattering from the leads and impurities give rise to sharp minima in the resistance of a bend, associated with subband thresholds. These minima are interpreted as a feature of the average resistance, unlike conductance fluctuations in disordered wires.