We have performed low-temperature measurements on a gated two-dimensional electron system in which electron-electron (e-e) interactions are insignificant. At low magnetic fields, disorder-driven movement of the crossing of longitudinal and Hall resistivities (ρxx and ρxy) can be observed. Interestingly, by applying different gate voltages, we demonstrate that such a crossing at ρxx ~ ρxy can oc...

p { margin-bottom: 0.1in; direction: rtl; line-height: 120%; text-align: right; }a:link { color: rgb(0, 0, 255); } In this paper, the reported experimental data related to electrical transport properties in bulk ZnO, ZnMgO/ZnO and ZnMgO/ZnO/ZnMgO single and double heterostructures were analyzed quantitavely and the most important scattering parameters on controlling electron concentratio...

Hydrogen doped In₂O₃ thin films were prepared by room temperature sputter deposition with the addition of H₂O to the sputter gas. By subsequent vacuum annealing, the films obtain high mobility up to 90 cm²/Vs. The films were analyzed in situ by X-ray photoelectron spectroscopy (XPS) and ex situ by X-ray diffraction (XRD), optical transmission and Hall effect measurements. Furthermore, we presen...

Resistivity and Hall effect measurements on nominally undoped Al0.25Ga0.75N/GaN/AlN heterostructures grown on sapphire substrates prepared by metal organic chemical vapor deposition have been carried out as a function of temperature (20–300 K) and magnetic field (0–1.4 T). Variable magnetic field Hall data have been analyzed using the improved quantitative mobility spectrum analysis technique. ...

We demonstrate noncontact measurements of the Hall mobility of doped semiconductor wafers with roughly 250 mm spatial resolution, using polarization rotation of focused beams of terahertz ~THz! radiation in the presence of a static magnetic field. Quantitative and independent images of both carrier density and mobility of a doped semiconductor wafer have been obtained. © 1997 American Institute...

We studied far-infrared ~FIR! response due to cyclotron resonance ~CR! of two-dimensional electron gas systems in GaAs/AlGaAs heterostructures by using cyclotron radiation from n-InSb devices as the illumination source. We examined the dependence of the FIR response on different experimental parameters, including the aspect ratio of Hall bars, electron mobility, bias current, illumination inten...

We present an experimental study of mesoscopic, two-dimensional electronic systems at high magnetic fields. Our samples, prepared from a low-mobility InGaAs/InAlAs wafer, exhibit reproducible, sample specific, resistance fluctuations. Focusing on the lowest Landau level, we find that, while the diagonal resistivity displays strong fluctuations, the Hall resistivity is free of fluctuations and r...

The π-conjugated backbone conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) is chemically doped to the conducting regime (σ ~ 30 S/cm) with poly(4-styrenesulfonate) (PSS). Construction of an all polymer FET is described and the time dynamics of a simple polymer channel device using aluminum as the gating material is discussed. On/off ratios approaching 10 are achieved but with relativ...

The electrical resistivity, Hall coefficient, and thermopower as functions of temperature are reported for lightly electron-doped Ca1−xLaxMnO3 0 x 0.10 . Unlike the case of hole-doped ferromagnetic manganites, the magnitude and temperature dependence of the Hall mobility H for these compounds is found to be inconsistent with small-polaron theory. The transport data are better described by the F...