Tuning the nonlinear optical properties of a 1D excitonic GaAs quantum dot system under a semi-parabolic potential with a detailed comparison with the experimental results: interplay of hydrostatic pressure and temperature

Suman Dahiya ; Siddhartha Lahon ; Rinku Sharma

Nanosistemy: fizika, himiâ, matematika, Tome 15 (2024) no. 5, pp. 632-642.

Résumé

The present study is dedicated to study the effect of Temperature and Hydrostatic Pressure on the absorption coefficient and refractive index of one-dimensional semi-parabolic excitonic GaAs QD’s by applying the compact density matrix formalism. Calculations are performed to obtain the excitonic state wave functions and energies in the strong confinement regime using the effective mass approximation. A significant dependence of nonlinear optical refractive index and absorption coefficient on hydrostatic pressure and temperature can be observed for excitonic and without excitonic case. Our investigations show that the peaks blue/red shifts are substantial when the excitonic interactions are taken into account. The opposite effects caused by temperature and pressure have substantial practical importance as they extend an alternative approach to tune and control the optical frequencies resulting from the transitions. The comparative analysis of the analytical optical properties of excitonic system facilitates the experimental identification of these transitions which are often close. We have attempted a comparison of the absorption coefficient obtained in the present work with experimental data at $T\cong10$ and $100$ K and found that the theoretical prediction is in agreement for $T\cong10$ K and it is in slight deviation from the experimental data for higher temperatures. The whole of these conclusions may have broad implications in future designing of Optoelectronic devices.

Détail

Keywords: quantum dot, exciton, nonlinear effects, hydrostatic pressure, temperature.
Mots-clés : nanostructures