Binding energies and optical absorption of donor impurities in spherical quantum dot under applied magnetic field


Al E. B., Kasapoglu E., Sakiroglu S., Sari H., Sokmen I., Duque C. A.

PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES, vol.119, 2020 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 119
  • Publication Date: 2020
  • Doi Number: 10.1016/j.physe.2020.114011
  • Journal Name: PHYSICA E-LOW-DIMENSIONAL SYSTEMS & NANOSTRUCTURES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, PASCAL, Applied Science & Technology Source, Compendex, Computer & Applied Sciences, INSPEC
  • Keywords: Spherical quantum dot, Magnetic field, Impurity binding energy, Optical absorption coefficient, REFRACTIVE-INDEX CHANGES, SPIN-ORBIT INTERACTION, MAGNETOOPTICAL PROPERTIES, HYDROGENIC DONOR, SINGLE DOPANT, COEFFICIENTS, STATES, GAAS, TRANSITIONS, SPECTRUM
  • Dokuz Eylül University Affiliated: Yes

Abstract

In this study, we have calculated the binding energies of the ground-ls and first few excited impurity states such as 2s, 1p, 2p, ld, and 2d, as well as the wave functions and energies of an electron in spherical quantum dot which has finite confinement potential under applied magnetic field. Furthermore, we calculated the impurity related optical absorption coefficients for 1s -> 1p, 1p -> 2s, 2s -> 2p, 1p -> 1d, and 2p -> 2d transitions between higher impurity states than those available in the literature. The calculations have been made in the framework of the effective mass approximation via the diagonalization method by using the complete basis of functions obtained as the exact solutions of the infinite QD in the absence of the magnetic field. Considering the two-level approach, the optical response was treated in the density matrix expansion. The results show that the external magnetic field strongly affects the impurity binding energies in large dot radii and the optical absorption coefficients. Furthermore, it has been observed that the change of dot radius has a significant effect on the optical absorption coefficients.