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Molecular Beam Epitaxy Of High Mobility In0.75Ga0.25As For Electron Spin Transport Applications, Paul J. Simmonds, S. N. Holmes, H. E. Beere, I. Farrer, F. Sfigakis, D. A. Ritchie, M. Pepper
Molecular Beam Epitaxy Of High Mobility In0.75Ga0.25As For Electron Spin Transport Applications, Paul J. Simmonds, S. N. Holmes, H. E. Beere, I. Farrer, F. Sfigakis, D. A. Ritchie, M. Pepper
Paul J. Simmonds
The authors describe the molecular beam epitaxy of relaxed, nominally undoped In0.75Ga0.25As–In0.75Al0.25As quantum well structures grown on InP substrates. The maximum two-dimensional electron density is 2 × 1011cm−2, with a peak mobility of 2.2 × 105cm2 V−1s−1 at 1.5K. In high magnetic field, the electron g-factor was shown to have a magnitude of 9.1 ± 0.1 at Landau-level filling factor of 4. The Rashba coefficient, determined from the analysis of the magnetoresistance at high Landau-level filling factor (>12), …
Spin-Orbit Coupling In An In0.52Ga0.48As Quantum Well With Two Populated Subbands, P. J. Simmonds, S. N. Holmes, H. E. Beere, D. A. Ritchie
Spin-Orbit Coupling In An In0.52Ga0.48As Quantum Well With Two Populated Subbands, P. J. Simmonds, S. N. Holmes, H. E. Beere, D. A. Ritchie
Paul J. Simmonds
Structural inversion asymmetry controls the magnitude of Rashba spin-orbit coupling in the electron energy spectrum of a narrow band gap semiconductor. We investigate this effect for a series of two-dimensional electron gases in In0.52Ga0.48As quantum wells, surrounded by In0.52Al0.48As barriers, where either one or two electric subbands are populated. Structural inversion asymmetry does not exist at low carrier density while at higher carrier densities (above (4–5) × 1011 cm−2), a finite spin splitting is observed. The spin orbit coupling coefficients (α) are determined from the power spectrum …
Quantum Transport In In0.75Ga0.25As Quantum Wires, P. J. Simmonds, F. Sfigakis, H. E. Beere, D. A. Ritchie, M. Pepper, D. Anderson, G. A.C. Jones
Quantum Transport In In0.75Ga0.25As Quantum Wires, P. J. Simmonds, F. Sfigakis, H. E. Beere, D. A. Ritchie, M. Pepper, D. Anderson, G. A.C. Jones
Paul J. Simmonds
In addition to quantized conductance plateaus at integer multiples of 2e2/h, the differential conductance G=dI/dV shows plateaus at 0.25(2e2/h) and 0.75(2e2/h) under applied source-drain bias in In0.75Ga0.25As quantum wires defined by insulated split gates. This observation is consistent with a spin-gap model for the 0.7 structure. Using a tilted magnetic field to induce Landau level crossings, the g factor was measured to be ~9 by the coincidence method. This material, with a mobility of 1.8×105 cm …