Study of the Diamagnetic Susceptibility of Core/Shell Type Semiconductor Nanostructures based on GaAs and Hg
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Description
In the present work, we have studied the diamagnetic susceptibility for a shallow donor confined to move in a Core/Shell Quantum Dot ’CSQD’. We have examined the form effects, magnetic field, impurity position and hydrostatic pressure effects. The calculations are performed in the framework of the effective mass approximation using the Hass variational approach. We describe the effect of the quantum confinement by an infinite deep potential.
For the form effects, we have studied the Spherical and Cylindrical Quantum Dot.
The results show that the diamagnetic susceptibility and the binding energy increase with the magnetic field. The form effect is more pronounced for larger QD. We remark that the diamagnetic susceptibility decreases when the impurity move from the center (one-center) to the surface (off-center). For a Core/ Shell (CCQD), we found that the diamagnetic susceptibility converges towards the limit -0.1 a.u when the ratio R1/R2 (R1 and R2 are the inner and the outer rays of the layer spherical) tends to 1. Our results show that diamagnetic susceptibility is strongly dependent on the magnetic field and on the donor position. The magnetic field effect is more appreciable, for large QDs.