We report the determination of the intrinsic spin-orbit interaction (SOI) parameters for In 0.53 Ga 0.47 As/In 0.52 Al 0.48 As quantum wells (QWs) from the analysis of the weak antilocalization effect. We show that the Dresselhaus SOI is mostly negligible in this system and that the intrinsic parameter for the Rashba effect, a SO ≡ α/ E z , is given to be a SO m * /m e = (1.46-1.51 × 10where α is the Rashba SOI coefficient, E z is the expected electric field within the QW, m * /m e is the electron effective mass ratio, and N S is the sheet carrier density. These values for a SO m * were also confirmed by the observation of beatings in the Shubnikov-de Haas oscillations in our most asymmetric QW sample.

We present a semiclassical interpretation of the time-reversal spin interference (SI) observed in the square loop arrays made of In 0.53 Ga 0.47 As quantum wells [T. Koga et al., Phys. Rev. B 74, 041302 (2006)]. The simulated amplitude of SI as a function of the Rashba parameter α captured characteristic features in the experimental results if γ 8 eVÅ 3 is assumed for the bulk Dresselhaus spin-orbit constant γ . Our work proves the validity of the semiclassical approach to predict the effect of time-reversal quantum interference in mesoscopic systems and the values of the spin-orbit coefficients recently deduced from the weak localization/antilocalization experiment.

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We report an approach for examining electron properties using information about the shape and size of a nanostructure as a measurement reference. This approach quantifies the spin precession angles per unit length directly by considering the time-reversal interferences on chaotic return trajectories within mesoscopic ring arrays (MRAs). Experimentally, we fabricated MRAs using nanolithography in InGaAs quantum wells which had a gate-controllable spin-orbit interaction (SOI). As a result, we observed an Onsager symmetry related to relativistic magnetic fields, which provided us with indispensable information for the semiclassical billiard ball simulation. Our simulations, developed based on the real-space formalism of the weak localization/antilocalization effect including the degree of freedom for electronic spin, reproduced the experimental magnetoconductivity (MC) curves with high fidelity. The values of five distinct electron parameters (Fermi wavelength, spin precession angles per unit length for two different SOIs, impurity scattering length, and phase coherence length) were thereby extracted from a single MC curve. The methodology developed here is applicable to wide ranges of nanomaterials and devices, providing a diagnostic tool for exotic properties of two-dimensional electron systems.

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