Dielectric mismatch and shallow donor impurities in GaN/HfO2 quantum
wells
PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES, (2015)DOI: 10.1016/j.physe.2014.10.005
Abstract
In this work we investigate electron-impurity binding energy in GaN/HfO2
quantum wells. The calculation considers simultaneously all energy
contributions caused by the dielectric mismatch: (i) image self-energy
(i.e., interaction between electron and its image charge), (ii) the
direct Coulomb interaction between the electron-impurity and (iii) the
interactions among electron and impurity image charges. The theoretical
model account for the solution of the time-dependent Schrodinger
equation and the results shows how the magnitude of the
electron-impurity binding energy depends on the position of impurity in
the well-barrier system. The role of the large dielectric constant in
the barrier region is exposed with the comparison of the results for
GaN/HfO2 with those of a more typical GaN/AIN system, for two different
confinement regimes: narrow and wide quantum wells. (C) 2014 Elsevier
B.V. All rights reserved.