Magnetotransport in quasi-ballistic narrow wires

We are studying quantum interference effects in narrow GaAs/AlGaAs wires of the quasi-ballistic regime, where the wire dimensions are comparable to or less than the phase coherence length of electron transport. By analysing the auto-correlation function of the universal conductance fluctuations in low field magnetoresistances, we obtained the wire-width and the magnetic field dependences of the correlation field and observed phase-coherence behaviors of electron waves. Estimating the boundary correlation field as ω_cτ = 1, we can discuss a mean free path in the split-gated wire. Such a boundary field analysis indicates a possibility of determination of the microscopic mean free path of quantum narrow wires.