Magnetoconductance of quantum wires

At low temperatures the conductance of a quantum wires exhibit characteristic plate\-aus due to the quantization of the transverse modes [1]. In the presence of high in-plane magnetic fields these spin-split transverse modes cross. Recently, these crossings were observed experimentally [2] via measurements of the differential conductance as a function of the gate voltage and the in-plane magnetic-field. These show structures described as either anti-crossings or magnetic phase transitions. Motivated by our previous works on magnetotransport in 2DEGs via the Spin Density Functional Theory (SDFT) [3], here we propose a similar model to investigate the magnetoconductance of quantum wires. We use (i) the SDFT via the Kohn-Sham self-consistent scheme within the local spin density approximation to obtain the electronic structure and (ii) the Landauer-Buettiker formalism to calculate the conductance of a quantum wire. Our results show qualitative agreement with the data of Ref.~[2]. \noindent [1] B.~J.~van Wees \textit{et al.}, Phys.~Rev.~Lett.~\textbf{60}, 848 (1988). \noindent [2] A.~C.~Graham \textit{et al.}, Phys.~Rev.~Lett. \textbf{100}, 226804 (2008). \noindent [3] H.~J.~P.~Freire, and J.~C.~Egues, Phys.~Rev.~Lett. \textbf{99}, 026801 (2007); G.~J.~Ferreira, and J.~Carlos Egues, J. Supercond. Nov. Mag., in press; G.~J.~Ferreira, H.~J.~P.~Freire, J.~Carlos Egues, submitted.