The Studies Of Electronic Structures In Quantum Dot Under The Constant Electric Field And Magnetic Field

Semiconductor quantum dot is a kind of three-dimensional confined structure with some special physical effects, such as quantum size confinement, quantum tunneling, coulomb blockade and so on. The electronic structures in semiconductor quantum dots are investigated in detail using the effective-mass approximation. The aim is to explore the physical mechanisms of the new effects in low-dimensional semiconductor systems, and to supply physical models and make the theoretical validity in designing novel quantum devices with better properties.In this thesis, we studied spectra of ground state and low-lying states in two-electron quantum dot by adopting harmonic potential. At first, we introduced the properties and development and applicant of quantum dot. In the second part, we got the energies and functions of ground state and low-lying states in the quantum dot by adopting quantum mechanics methods, and then got the relation between energy and different confining potential and different characteristic length. When considering the Coulomb interaction, we may get different relation on energies; what's more, we will find stark effect in an electric field. In the third part, we studied different spectra of ground state and low-lying states in the quantum dot under the magnetic field. At last, we got some conclusions on the properties of quantum dots.Comparing system with different confining potential and different characteristic length of quantum dots on the spectra are revealed. Our studies show that whether the magnetic and electric field being in quantum dots affects the spectra of the system. The all results indicate that the property of quantum dots system with confining potential is rather sensitive to the strength of the confinement potential. The present results are useful to understand the optical and magnetic properties of quantum dots.