https://doi.org/10.1140/epjb/e2012-20435-6
Regular Article
Hydrogenic donor impurity in a cubic quantum dot: effect of position-dependent effective mass
Department of Physics, College of Sciences, Yasouj
University, 75914-353
Yasouj,
Iran
a e-mail: khordad@mail.yu.ac.ir
Received:
6
June
2011
Received in final form:
14
December
2011
Published online:
4
April
2012
In this paper, we intend to study the effect of variable mass on the binding energy. In this regard, we apply an analytic expression for position-dependent effective mass in a cubic quantum dot. Then, we obtain the binding energies of a shallow donor in the quantum dot of GaAs/AlxGa1−xAs using a variational procedure within the effective mass approximation. Calculations are presented with a constant effective mass and position-dependent effective mass. It is found that (i) the binding energy decreases as the dot length increases in both the cases of constant and variable masses, (ii) an increase of binding energy is observed when the spatially varying mass is included, and (v) the binding energy shows complicated behavior when the position-dependent mass is included for the small dot size L ≤ 130 Å.
Key words: Solid State and Materials
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2012