Simultaneous Effects of Hydrostatic Pressure and Temperature on Donor Impurity States in Wurtzite InxGa1-xN/GaN Concentric Double Quantum Rings

摘要

In the framework of effective mass approximation, the ground-state donor binding energies in a wurtzite InxGa1-xN/GaN concentric double quantum rings are calculated by using a variational technique. In the calculation, the combined effects of hydrostatic pressure and temperature on material parameters (e.g., the conduction band offset, the electron effective masses, the static dielectric constants, and the phonon frequencies) are included. We found that: (i) the built-in electric field of well and/or barrier exhibits an increasing behavior when the hydrostatic pressure is augmented. (ii) when an impurity ion in symmetric surface of the concentric double quantum rings is located at the centre of inner ring, the ground-state donor binding energy increases gradually with the augment of the hydrostatic pressure and/or the temperature; (iii) the ground-state donor binding energy exhibits a maximum value with increasing the structure parameters (the radii of inner and/or outer ring, and the height) of the concentric double quantum rings; (iv) the donor binding energy as a function of the radial impurity position is analyzed in a wurtzite InxGa1-xN/GaN concentric double quantum rings.