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arXiv · 1410.4213

Dielectric mismatch and shallow donor impurities in GaN/HfO2 quantum wells

T. A. S. Pereira·A. A. Sousa·M. H. Degani·G. A. Farias
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Abstract

In this work we investigate electron-impurity binding energy in GaN/HfO$_2$ 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 Schrödinger 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/HfO$_2$ with those of a more typical GaN/AlN system, for two different confinement regimes: narrow and wide quantum wells.

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T. A. S. Pereira, A. A. Sousa, M. H. Degani, G. A. Farias. 2014-10-15. Dielectric mismatch and shallow donor impurities in GaN/HfO2 quantum wells. https://doi.org/10.1016/j.physe.2014.10.005

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