Exploring optical refractive index change of impurity doped quantum dots driven by white noise

• Published in: Superlattices and microstructures Vol. 88; pp. 620 - 633
• Main Authors: Saha, Surajit, Pal, Suvajit, Ganguly, Jayanta, Ghosh, Manas
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.12.2015
• Subjects: Gaussian white noise; Impurity; Noise strength; Quantum dot; Total refractive index change; Gaussian white noise; Quantum dot; Impurity; Total refractive index change; Noise strength
• ISSN: 0749-6036; 1096-3677
• DOI: 10.1016/j.spmi.2015.10.021

We make an extensive exploration of total refractive index (RI) change of impurity doped quantum dots (QDs) in presence and absence of noise. The noise invoked in the present study is a Gaussian white noise. The quantum dot is doped with repulsive Gaussian impurity. Noise has been incorporated to the system additively and multiplicatively. A perpendicular magnetic field acts as a source of confinement and a static external electric field has been applied. The total RI change profiles have been studied as a function of incident photon energy when several important parameters such as optical intensity, electric field strength, magnetic field strength, confinement energy, dopant location, relaxation time, Al concentration, dopant potential, and noise strength assume different values. Additionally, the role of mode of application of noise (additive/multiplicative) on the total RI change profiles has also been examined minutely. The total RI change profiles mainly comprise of interesting observations such as shift of total RI change peak position and maximization/minimization of peak intensity. However, presence of noise conspicuously alters the features of total RI change profiles through some interesting manifestations. Moreover, the mode of application of noise (additive/multiplicative) also governs the total RI change profiles in diverse as well as often contrasting manners. The observations indicate possibilities of tailoring the linear and nonlinear optical properties of doped QD systems in presence of noise. [Display omitted] •Total refractive index (RI) change of impurity doped quantum dot is studied.•The dot is subject to Gaussian white noise.•Total RI change is affected by various important parameters.•Noise influences total RI change profiles noticeably.•Findings may have technological importance.