2004/11/29 by F. Fischer, M. Grayson, D. Schuh +3
Physics and Astronomy · #Physics of Superconductivity and Magnetism #Quantum and electron transport phenomena #Semiconductor Quantum Structures and Devices #cond-mat.mes-hall #cond-mat.mtrl-sci
paper · pdf · doi:10.1063/1.1923761
published as Appl. Phys. Lett. 86, 192106 (2005) · 4 pages, 4 figures
arxiv created 2004/11/29 · openalex publication_date 2005/05/03 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We implement metallic layers of Si-doped (110) GaAs as modulation doping in high mobility p-type heterostructures, changing to p-growth conditions for the doping layer alone. The strongly autocompensated doping is characterized in bulk samples first, identifying the metal-insulator transition density and confirming classic hopping conduction in the insulating regime. To overcome the poor morphology inherent to Si p-type (110) growth, heterostructures are then fabricated with only the modulation-doping layer grown under p-type conditions. Such heterostructures show a hole mobility of μ=1.75×105cm2∕Vs at density p=2.4×1011cm−2. We identify the zero-field spin-splitting characteristic of p-type heterostructures, but observe a remarkably isotropic mobility and a persistent photoconductivity unusual for p heterojunctions grown on other facets. This modulated growth technique is particularly relevant for p-type cleaved-edge overgrowth and for III-V growth chambers, where Si is the only dopant.