Donor impurity states and related optical responses in triangular quantum dots under applied electric field

Kasapoglu E., Ungan F., Sari H., Sokmen I., Mora-Ramos M. E., Duque C. A.

SUPERLATTICES AND MICROSTRUCTURES, vol.73, pp.171-184, 2014 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 73
  • Publication Date: 2014
  • Doi Number: 10.1016/j.spmi.2014.05.023
  • Journal Name: SUPERLATTICES AND MICROSTRUCTURES
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.171-184
  • Dokuz Eylül University Affiliated: Yes

Abstract

The linear and nonlinear coefficients for the optical absorption and relative refractive index change associated with transitions between donor impurity states in a two-dimensional quantum dot of triangular shape under applied electric field are calculated for y-polarization of the incident light. Both the effective mass and parabolic band approximations have been considered. The results show that the application of a DC electric field strengthens the impurity-related optical absorption response, with particular relevance in the case of the nonlinear contribution to it. However, for a fixed donor atom position inside the triangular quantum dot, the calculations show that the in-plane orientation of the applied field can becomes a critical parameter that may lead to a strong quenching of the interstate light absorption. (C) 2014 Elsevier Ltd. All rights reserved.