Abstract
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× 105 cm2 V s at density p=2.4× 1011 cm-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.
| Original language | English (US) |
|---|---|
| Article number | 192106 |
| Pages (from-to) | 1-3 |
| Number of pages | 3 |
| Journal | Applied Physics Letters |
| Volume | 86 |
| Issue number | 19 |
| DOIs | |
| State | Published - May 9 2005 |
Funding
This work was supported financially by Deutsche Forschungsgemeinschaft via Schwerpunktprogramm Quantum-Hall-Systeme and in the framework of the COLLECT EC-Research Training Network HPRN-CT-2002-00291. M. G. is grateful to A. Yacoby for motivatingdiscussions.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)