A new confinement potential in spherical quantum dots: Modified Gaussian potential

Abstract A new confinement potential for spherical quantum dots, called the modified Gaussian potential (MGP), is studied. In the present work, the following problems are investigated within the effective-mass approximation: (i) the one-electron energy spectra, (ii) wave functions, (iii) the problem of existence of a bound electron state, and (iv) the binding energy of center and off-center hydrogenic donor impurities. For zero angular momentum ( l = 0 ) , the new confinement potential is sufficiently flexible to obtain analytically the spectral energy and wave functions. The results obtained from the present work show that (i) the new potential is suitable for predicting the spectral energy and wave functions, and (ii) the geometrical sizes of the quantum dot play the important roles on the energy levels, wave functions, the binding energy, and the existence of a bound electron state.

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