https://doi.org/10.1140/epjb/e2011-20466-5
Regular Article
Optical absorption and refraction index change of a confined exciton in a spherical quantum dot nanostructure
1
Department of Physics, St. Michael College of Engg. & Tech,
630551
kalaiyarkoil,
India
2
Department of Physics, Govt. Arts College, 625106
Melur, Madurai, India
3
Department of Chemical Engineering and Green Energy Center,
College of Engineering, Kyung Hee University, 1 Seochun, Gihung, Yongin, 446-701
Gyeonggi, S.
Korea
a e-mail: a.john.peter@gmail.com
Received:
14
June
2011
Received in final form:
11
October
2011
Published online:
23
November
2011
Electronic energies of an exciton confined in a strained Zn1−xCdxSe/ZnSe quantum dot have been computed as a function of dot radius with various Cd content. Calculations have been performed using Bessel function as an orthonormal basis for different confinement potentials of barrier height considering the internal electric field induced by the spontaneous and piezoelectric polarizations. The optical absorption coefficients and the refractive index changes between the ground state (L = 0) and the first excited state (L = 1) are investigated. It is found that the optical properties in the strained ZnCdSe/ZnSe quantum dot are strongly affected by the confinement potentials and the dot radii. The intensity of the total absorption spectra increases for the transition between higher levels. The obtained optical nonlinearity brings out the fact that it should be considered in calculating the optical properties in low dimensional semiconductors especially in quantum dots.
© EDP Sciences, Società Italiana di Fisica and Springer-Verlag, 2011