2022/07/05 by Metti, S., Thomas, C., Xiao, D. +1 · 1 citation
#Applied Physics (physics.app-ph) #FOS: Physical sciences #Mesoscale and Nanoscale Physics (cond-mat.mes-hall)
paper · doi:10.48550/arxiv.2207.02006
InSb1-xAsx is a promising material system for exploration of topological superconductivity in hybrid superconductor/semiconductor devices due to large effective g-factor and enhanced spin-orbit coupling when compared to binary InSb and InAs. Much remains to be understood concerning the fundamental properties of the two-dimensional electron gas (2DEG) in InSbAs quantum wells. We report on the electrical properties of a series of 30 nm InSb1-xAsx quantum wells grown 40 nm below the surface with three different arsenic mole fractions, x = 0.05, 0.13 and 0.19. The dependencies of mobility on 2DEG density and arsenic mole fraction are analyzed. For the x = 0.05 sample, the 2DEG displays a peak mobility μ = 2.4 × 105 cm2/Vs at a density of n = 2.5 × 1011 cm-2. High mobility, small effective mass, and strong spin-orbit coupling result in beating in the Shubnikov de Hass oscillations at low magnetic field. Fourier analysis of the Shubnikov de Haas oscillations facilitates extraction of the Rashba spin-orbit parameter α as a function of 2DEG density and quantum well mole fraction. For x = 0.19 at n = 3.1 × 1011 cm-2, α ≈ 300 meVÅ, among the highest reported values in III-V materials.