Anisotropic weak anti-localization under in-plane magnetic field and control of dimensionality via spin precession length

We have examined the newly proposed method in order to electrically deduce the ratio between the Rashba and Dresselhaus spin-orbit interaction (SOI) parameters. Anisotropic magneto-conductance in gate-fitted InGaAs narrow wires is observed under an in-plane magnetic field. From the comparison between experiments and calculated Rashba SOI parameters, we have found that the method is applicable only when the wire width is shorter than the spin precession length. A transition from narrow wires to two-dimensional (2D) wires is observed both by decreasing the spin precession length and by increasing wire width.