Growth and electrical characterization of Al0.24Ga0.76As/AlxGa1-xAs/Al0.24Ga0.76As modulation-doped quantum wells with extremely low x

Geoff C. Gardner, Birck Nanotechnology Center, Purdue University
John D. Watson, Birck Nanotechnology Center, Purdue University
Sumit Mondal, Birck Nanotechnology Center, Purdue University
Nianpei Deng, Purdue University
Gabor A. Csathy, Purdue University
Michael J. Manfra, Birck Nanotechnology Center, Purdue University

Date of this Version



Copyright 2013 American Institute of Physics. This article may be downloaded for personal use only. Any other use requires prior permission of the author and the American Institute of Physics. The following article appeared in Appl. Phys. Lett. 102, 252103 (2013); and may be found at The following article has been accepted by Applied Physics Letters. Copyright 2013 Geoffrey C. Gardner, John D. Watson, Sumit Mondal, Nianpei Deng, Gabor A. Csáthy and Michael J. Manfra. This article is distributed under a Creative Commons Attribution 3.0 Unported License.


We report on the growth and electrical characterization of modulation-doped Al0.24Ga0.76As/AlxGa1-xAs/Al0.24Ga0.76As quantum wells with mole fractions as low as x = 0.00057. Such structures will permit detailed studies of the impact of alloy disorder in the fractional quantum Hall regime. At zero magnetic field, we extract an alloy scattering rate of 24 ns(-1) per% Al. Additionally, we find that for x as low as 0.00057 in the quantum well, alloy scattering becomes the dominant mobility-limiting scattering mechanism in ultra-high purity two-dimensional electron gases typically used to study the fragile nu = 5/2 and nu = 12/5 fractional quantum Hall states. (C) 2013 AIP Publishing LLC.


Nanoscience and Nanotechnology