ISSN:
1434-6036
Keywords:
PACS. 72.80.Ey III-V and II-VI semiconductors – 73.43.Qt Magnetoresistance – 72.20.Ee Mobility edges; hopping transport
Source:
Springer Online Journal Archives 1860-2000
Topics:
Physics
Notes:
Abstract: We present measurements of the diagonal Rxx and off-diagonal Rxy magnetoresistance under quantum Hall conditions on several high electron mobility transistors (HEMT) based on InxGa1-xAs quantum wells. From the magnetoresistance tensor we obtain the longitudinal conductivity σ xx . We study the transport mechanisms near the σ xx minima at temperatures ranging between 2 K and 35 K; activated transport is the dominant mechanism for temperatures above 7 K while variable range hopping conductivity is significant for lower temperatures. We show that electron-electron correlations should be taken into account to explain the conductivity vs temperature behaviour below 5 K. Finally, we study the behaviour of the localization length as a function of Landau level filling and obtain a critical exponent γ = 3.45±0.15.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/s10051-001-8699-9
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