Abstract
We present in this Brief Report our experimental results on the quantum Hall plateau-to-plateau transition in long-range Coulombic disordered two-dimensional electron systems embedded in the AlxGa 1-xAs-Al0.32Ga0.68 As heterostructures (with x=0% and 0.21%) in a large temperature range from 1.2 K down to 1 mK. In these samples a crossover behavior is observed from the high-temperature, nonuniversal scaling regime to the low-temperature, universal scaling regime, with the temperature exponent κ changing from κ=0.58 to 0.42, respectively. The crossover temperature increases with increasing x, from 120 mK for x=0% to 250 mK for x=0.21%. When the Al concentration reaches x=0.85% at which the short-range random alloy potential dominates the disorder, the crossover temperature is beyond 1.2 K and the universal scaling is observed over two decades of temperature.
Original language | English (US) |
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Article number | 033305 |
Journal | Physical Review B - Condensed Matter and Materials Physics |
Volume | 81 |
Issue number | 3 |
DOIs | |
State | Published - Jan 20 2010 |
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics