Mollow triplet in Two-Impurity dumbbell quantum dot

Quantum dots (QDs), renowned for their unique electronic and optical properties, are finding innovative applications in areas such as bioimaging, quantum computing, and light-emitting diodes. This study focuses on biconical (QD), which offer enhanced control over charge carrier confinement, leading to greater tunability of their electronic and optical properties. Utilizing numerical discretization within the effective-mass approximation, the research accurately calculates excitonic properties in these complex systems, particularly in GaAs biconical QDs. Additionally, the photoluminescence properties of these biconical QDs show promise as tunable light sources, with the added benefit of electric field influence for photoluminescence.The research also explores the energy dependence on bicone geometry, highlighting energy coincidence as the two cones' heights match. Photoluminescence investigations, conducted on biconical QDs of varying sizes under different electric field conditions, confirm the expected red and blue shifts based on the field direction.In conclusion, this study establishes a theoretical foundation for manipulating the properties of biconical QDs, opening avenues for their application in optoelectronic devices. The ability to control photoluminescence shifts through electric field direction underscores the practical significance of this research.

Photoluminescence spectra in GaAs biconical quantum dots

Gavalajyan

2024

Single electron states and intraband absorption in dumbbell quantum dot

Yengibaryan

2024

In this study, we investigated electronic properties of a dumbbell-shaped quantum dot (QD) made from gallium arsenide. For this purpose, we employ the finite element method. Our investigation begins by calculating the wave functions and energies of the ground state and the first nine excited states. This allows us to understand how the quantum dot's shape impacts its electronic structure. Based on the obtained results for the wave functions and energies of one electron, we calculated the oscillator strengths for different quantum transitions. We discover that the most pronounced absorption occurs during transitions between the ground state and the second, third, eighth, and ninth excited states. Additionally, we analyzed the absorption processes between these energy levels and revealed the dependence of the absorption coefficient for the intraband transitions dumbbell-shaped QD on the energy of the incident light.

The role of geometry in tailoring the linear and nonlinear optical properties of semiconductor quantum dots

Mantashian

2024

The paper aims to reveal the relationship between the geometrical features and linear and nonlinear optical properties of InAs quantum dots (QDs). This problem is justified by the extreme variety offered by the recent advances in growth techniques tailored to the attainment of QDs and nanostructures with virtually any shape. To that end, the Finite Element Method in conjunction with the Effective Mass Approximation and Envelope Function Approximation was employed to solve the one-particle eigenproblems in domains with any complex geometries. The paper explores nanoplatelets, spherical QDs, nanocones, nanorods, nanotadpoles, and nanostars. It has been found that there is a clear correlation between the complexity and symmetry of the QDs and their linear and nonlinear absorption spectra for transitions between the electronic ground state and the first three excited states.