Tuning electronic and magnetic properties of off-center D− impurity in GaAs quantum dots with spin–orbit interactions and magnetic field

• We study the ground state energy and binding energy of an off-center D - impurity in a quantum dot with Gaussian confinement in the presence of the magnetic field (MF) and spin–orbit interactions (SOIs). • We rigorously determine the ground state and ground state binding energies using a variational method and compare the dimensionality. • The magnetic moment and susceptibility, and resultant dipole moment are also determined. • Phase diagrams map stable two-electron binding ranges, enabling tunable donor-bound states for quantum device applications. • It is found that the MF, SOIs, confinement depth and range, and electron–electron coupling are important factors that significantly influence the electronic and magnetic properties of the D - impurity in a quantum dot. Our investigation into the electronic, magnetic, and correlation properties of an off-center negatively charged donor D - in a GaAs quantum dot with Gaussian confinement is a novel and intriguing area of research. Conducted under the influence of Rashba and Dresselhaus spin–orbit interactions and an external magnetic field, we have derived analytical expressions for ground-state energy, binding energy, dipole moment, and pair correlation function using the effective mass approximation and Ritz variational approach. The binding energy peaks when the impurity is centered and decreases with off-center displacement, potentially leading to an unbound state. Dresselhaus spin–orbit interaction enhances binding at the dot’s center, while Rashba spin–orbit interaction dominates with larger displacements, inducing charge asymmetry that impacts electronic and spintronic properties. Magnetic fields strengthen electron localization, potentially restoring binding in less favorable configurations. Impurity position and spin–orbit interactions significantly influence dipole moment and electron–electron correlation. Phase diagrams delineate parameter ranges for stable two-electron binding, offering novel insights into tunable donor-bound states for quantum device applications.