JP Journal of Solids and Structures
Volume 2, Issue 2, Pages 177 - 189
(July 2008)
|
|
SPACE-CHARGE EFFECTS ON THE MAGNETOCONDUCTANCE AND THERMOPOWER OF A TWO-DIMENSIONAL ELECTRON SYSTEM
G. C. Kostakis (Greece) and P. C. Divari (Greece)
|
Abstract:
We calculate the conductance and thermopower of a 2DES in the presence of both a space-charge distribution and a uniform magnetic field using an adiabatic approximation method under the conditions of ballistic transport. A parabolic electrostatic potential, arising from a uniform space-charge density generated from donor or acceptor impurities, is considered. The effects of space-charge distribution on the magnetoconductance quantization as well as on the thermopower oscillations are investigated. With space-charge density increasing, the conductance as a function of Fermi energy exhibit broadened plateaus corresponding to smaller quantized values. Thermopower in the presence of magnetic field shows typical resonant structure and, as the space-charge density increases, the peak values are greater and the intervals between adjacent peaks are broadened. The effects of temperature and applied electric fields are also discussed. |
| Keywords and phrases: semiconductor structures, magnetoconductance, thermopower, 2DEG. |
| |
| Number of Downloads: 156 | Number of Views: 435 |
|
