Impact of Applied Temperature and Hydrostatic Pressure on the Off-Center Donor Spectrum in Spherical Quantum Dot

Abstract

Within the effective mass approximation and the infinite confinement potential, this work focused on studying the electronic properties of spherical quantum dot (SQD) nanostructure through the finite difference method. The effects of shallow donor impurity position, temperature (T), and hydrostatic pressure (P) on the binding energy, the electron spatial extension <re> and the average electron-impurity distance <rD-e> in a SQD have been evaluated. Our findings show that the binding energy increases as a function of hydrostatic pressure and decreases with the temperature effect. However, the binding energy presents very clear maximum around the spherical nanostructure center depending on the impurity position. For higher SQD, the impact of externals perturbations (P and T) on the electron spatial extension are more significant. The distance <re> decreases with the augmentation of hydrostatic pressure when the impurity is near the center, which is conversely when the impurity is near the edge. In addition, applying the hydrostatic pressure and temperature leads to decreasing and increasing the average distance <rD-e>, respectively.

Donor Atom Properties in 2D Ultra-Thin Cylindrical Quantum Dots

“…This behavior leads us to deduce that the decrease of the height produces a strong confinement of the electron probability density, therefore a very important energy detected. A similar behavior occurs in other low dimensional systems such as Quantum rings [26,27].…”

“…This has enabled the study of fundamental properties of zero-dimensional systems and has created opportunities for new devices in various application areas [3][4][5]. These nanostructures have been studied by using different methos such as variational, finite difference and element methods [6][7][8][9][10][11][12][13][14][15]. For 2D ultra-thin quantum dot (QD) structures, the electronic and optical properties of these systems are different from those of flat two-dimensional electronic systems.…”

The Effect of a Single Off-Center Shallow Donor Atom on the Binding Energy and Diamagnetic Susceptibility in a GaAs Horn Torus Quantum Dot

“…Many researchers have studied the effect of the position of the impurity on physical parameters such binding energy, dipole moment, donor energy and diamagnetic susceptibility. Their common results on a symmetric behavior when the impurity moves on a symmetric geometry, on the other hand a non-symmetric behavior when the symmetry of the geometry is broken [25][26][27][28][29]. The finite difference method (FDM) has been applied to a large study, due to its simplicity and high accuracy [29][30][31].…”

“…Their common results on a symmetric behavior when the impurity moves on a symmetric geometry, on the other hand a non-symmetric behavior when the symmetry of the geometry is broken [25][26][27][28][29]. The finite difference method (FDM) has been applied to a large study, due to its simplicity and high accuracy [29][30][31]. To our knowledge, the study of the donor impurity confined in a Horn Torus quantum dot (HnTQD) has not yet been carried out.…”