Finite element analysis of multilayered spherical quantum dots: Effects of layer dimensions, alloy composition, and relaxation time on the linear and nonlinear optical properties.

This study delves into the optical characteristics of multilayered spherical quantum dots (MLSQDs). By employing the finite element method, we systematically explore the impact of varying layer dimensions, the A l -concentration, and the intersubband relaxation time on the linear, third nonlinear, and total optical absorption coefficients and refractive index changes within this nanostructure. Our findings reveal intriguing correlations between the sizes of individual layers and the resultant optical responses. Notably, subtle adjustments in layer dimensions manifest profound changes in both linear and third-order nonlinear absorption coefficients. Furthermore, the investigation of relaxation time elucidates the key role it plays in changing optical properties, illustrating how relaxation time influences the optical behavior of MLSQDs. This study provides a comprehensive understanding of the impact of layer sizes, relaxation time, and A l concentration on the optical properties of MLSQDs. These findings offer valuable guidance for engineering customized optical functionalities in nanophotonic technologies. • The OAC peaks shift red with increased core radius, then blue shifts at larger sizes. • The OACs and RICs generally follow the trends observed in the transition energy. • Higher relaxation times lead to stronger and sharper absorption peaks. • A l -concentration is another dimension to the control and tuning of QD properties.. [ABSTRACT FROM AUTHOR]