Combined effects of electric and magnetic fields on confined donor states in a diluted magnetic semiconductor parabolic quantum dot
Zhejiang Institute of Modern Physics, Zhejiang University, Hangzhou, 310027, P.R. China
2 School of Physics, Madurai-Kamaraj University, Madurai, 625021, India
Corresponding author: a email@example.com
Published online: 27 October 2006
A variational formalism for the calculation of the binding energies of hydrogenic donors in a parabolic diluted magnetic semiconductor quantum dot is discussed. Results are obtained for Cd1-xin Mnxin Te/Cd1-xout MnxoutTe structures as a function of the dot radius in the presence of external magnetic and electric fields applied along the growth axis. The donor binding energies are computed for different field strengths and for different dot radii. While the variation of impurity binding energy with dot radii and electric field are as expected, the polarizability values enhance in a magnetic field. However, for certain values of dot radii and in intense magnetic fields the polarizability variation is anomalous. This variation of polarizability is different from non- magnetic quantum well structures. Spin polaronic shifts are estimated using a mean field theory. The results show that the spin polaronic shift increases with magnetic field and decreases as the electric field and dot radius increase.
PACS: 75.50.Pp – Magnetic semiconductors / 73.21.La – Quantum dots / 78.67.Hc – Quantum dots
© EDP Sciences, Società Italiana di Fisica, Springer-Verlag, 2006