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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), …
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 …
Growth-Temperature Optimization For Low Carrier-Density In0.75Ga0.25As-Based High Electron Mobility Transistors On Inp, Paul J. Simmonds, H. E. Beere, D. A. Ritchie, S. N. Holmes
Growth-Temperature Optimization For Low Carrier-Density In0.75Ga0.25As-Based High Electron Mobility Transistors On Inp, Paul J. Simmonds, H. E. Beere, D. A. Ritchie, S. N. Holmes
Paul J. Simmonds
Two-dimensional electron gases (2DEGs) were formed in undoped In0.75Al0.25As / In0.75Ga0.25As / In0.75Al0.25As quantum wells. The optimal growth temperature for this structure is 410°C, with peak 2DEG electron mobility and density values of μ = 221000 cm2/V s and n = 1.36 × 1011 cm−2 at 1.5 K. This electron mobility is equal to the highest previously published for these undoped structures but with a factor of 2 reduction in n. This has been achieved through the use of a significantly thinner InAlAs …