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Excitation in quantum dots is an important phenomenon. Realizing the importance we investigate the excitation behavior of a repulsive impurity-doped quantum dot induced by simultaneous oscillations of impurity potential and spatial stretch of impurity domain. The impurity potential has been assumed to have a Gaussian nature. The ratio of two oscillations (

Nowadays we frequently encounter a plethora of theoretical and experimental researches on impurity states in low-dimensional heterostructures [

Driven by the emergence of novel experimental and theoretical techniques along with the existing ones, the research on carrier dynamics in nanodevices has become a ubiquitous field. The internal transitions between impurity-induced states in a QD led to research on carrier dynamics [

The aspects discussed above have urged us to investigate thoroughly excitation in doped quantum dots. As a result, of late, we have made some investigations on the excitation profiles of the doped quantum dots which were initiated by a time-dependent fluctuation of the impurity potential (

We consider the energy eigenstates of an electron subject to a harmonic confinement potential

Following earlier works on the effects of a repulsive scatterer in multicarrier dots in the presence of magnetic field [

We write the trial wave function

The general expression for the matrix elements of

We can now introduce the time dependence into the impurity potential and impurity domain so that

Under the perturbation, the evolving wave function is described by a linear combination of the eigenstates of

At the very outset of the discussion it needs to be realized that the excitation rate is controlled by the interplay between several factors of different characteristics. As the dopant is introduced at a greater distance from the dot confinement center (

Plot of

Let us now have a close look at the plot that delineates the time-average excitation rate (

Plot of

For an on-center dopant there is a considerable extent of dot-impurity overlap so that the role of

At near off-center dopant location the dot-impurity overlap gets somewhat reduced. Interestingly, at this dopant location we envisage saturation-like behavior of the excitation rate at both low and high

For a far off-center dopant the excitation rate profile is endowed with a minima in the vicinity of

The important message hitherto received by us is that beyond

Plot of

In the present inspection the importance of dopant coordinate on excitation profile becomes perspicuous. In this connection the notable works of Baskoutas et al. [

Plot of

The excitation profile of repulsive impurity-doped quantum dots triggered by simultaneous oscillations of impurity potential, and impurity spread unveils noteworthy features. The ratio of two oscillations (

The authors S. Pal and M. Ghosh thank D. S. T-F. I. S. T (Govt. of India) and U. G. C.-S. A. P (Govt. of India) for partial financial support. Thanks are also due to Mr. Nirmal Kr Datta for his help.

^{2+}ions in cubic

^{2+}doped ZnS nanocrystals self-assembled in a tight mesoporous structure