0.7-anomaly and magnetotransport of disordered quantum wires

Authors :: Czapkiewicz, M.
Zagrajek, P.
Wrobel, J.
Grabecki, G.
Fronc, K.
Dietl, T.
Ono, Y.
Matsuzaka, S.
Ohno, H.
Source :: Europhys. Lett., 82 (2008) 27003
Publication Year :: 2007
Abstract: The unexpected "0.7" plateau of conductance quantisation is usually observed for ballistic one-dimensional devices. In this work we study a quasi-ballistic quantum wire, for which the disorder induced backscattering reduces the conductance quantisation steps. We find that the transmission probability resonances coexist with the anomalous plateau. The studies of these resonances as a function of the in-plane magnetic field and electron density point to the presence of spin polarisation at low carrier concentrations and constitute a method for the determination of the effective g-factor suitable for disordered quantum wires.<br />Comment: 4 pages, 6 figures