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Journal of Contemporary Physics (Armenian Academy of Sciences)

Investigation of Biexciton Induced Linear and Nonlinear Refractive Index Changes in Ellipsoidal Quantum Dot

Yuri Y. Bleyan

Published Dec 1, 2022• 1 citation
Publisher

Abstract

Abstract The biexciton states of the ground and excited levels in a GaAs strongly oblate ellipsoidal quantum dot are studied with the use of the variational method. The trial variational wave function of the biexciton is constructed on single-particle wave functions, obtained within the geometrical adiabatic approximation. The biexciton energies are obtained from the geometric parameters of an ellipsoidal quantum dot for both the ground and excited states. The linear and nonlinear refractive indexes of the biexciton around one- and two-photon resonances are calculated as the real parts of the first- and third-order nonlinear susceptibilities, respectively. The spectra of changes of the biexciton refractive index for transitions between ground states as a function of the photon energy are obtained for different values of the small semiaxis of the ellipsoidal quantum dot.

DOI
10.1134/s1068337222040065

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