On the origin of carrier localization on two-dimensional GaN substitution layers embedded in GaAs

The electronic properties of a nitrogen atomic layer embedded in GaAs are studied by means of the empirical pseudopotential (EPP) method in a periodic modelling approach. The electronic properties of a nitrogen atomic layer embedded in GaAs are studied by means of the empirical pseudopotential (EPP) method in a periodic modelling approach. They are found to be anomalous, compared with other A(III)–B(V)-semiconductors containing isovalent atomic substitution layers. Namely, the nitrogen layer induces not only one but two localized states inthe lower conductionban d regionof the GaAs host material. It is shown that this anomaly originates from chemical and size e3ects associated with the nitrogen substitution layer. These theoretical results can be correlated with 4rst experimental investigations on the GaN/GaAs-system.