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Updated: Jun 3, 2026
12:57
Resonance Fluorescence of an InGaAs Quantum Dot in a Planar Cavity Using Orthogonal Excitation and Detection
Published on: October 13, 2017
On the anomalous Stark effect in a thin disc-shaped quantum dot.
A Oukerroum1, E Feddi, J Bosch Bailach
1Laboratoire de Physique de la Matière Condensée, Faculté des Sciences et Techniques, Bd Yassima, 28820 Mohammedia, Morocco.
Summary
A lateral electric field significantly impacts exciton behavior in InAs quantum dots. Calculations reveal field-induced polarization enhances exciton lifetime, offering insights into quantum dot optical properties.
Area of Science:
- Condensed Matter Physics
- Quantum Optics
- Materials Science
Background:
- Excitons in semiconductor quantum dots are crucial for optoelectronic devices.
- Understanding the influence of external fields on exciton states is vital for device engineering.
- InAs disc-shaped quantum dots offer unique confinement properties.
Purpose of the Study:
- To investigate the effect of a lateral external electric field (F) on the exciton ground state in InAs disc-shaped quantum dots.
- To analyze the contributions of linear and quadratic terms of the electric field to the lateral Stark shift.
- To determine the exciton's lateral permanent dipole moment and polarizability and their dependence on disc size.
Main Methods:
- Employed a variational method within the effective mass approximation.
- Modeled the quantum dot as a large-radius disc (2D harmonic oscillator) with a finite height (infinite square well).
- Analyzed the excitonic Hamiltonian, separating lateral confinement and growth direction effects.
Main Results:
- The lateral Stark shift is accurately described by both linear and quadratic terms of the electric field, indicating a nonzero lateral dipole moment and polarizability.
- Calculated values for the lateral permanent dipole moment and polarizability were obtained and correlated with disc dimensions.
- The optical integral analysis showed an increased exciton lifetime under the applied electric field due to field-induced polarization.
Conclusions:
- External lateral electric fields significantly modify exciton properties in InAs quantum dots.
- The study quantifies the exciton's lateral dipole moment and polarizability, providing essential parameters for device design.
- Field-induced polarization enhances exciton lifetime, suggesting potential for improved quantum dot-based optoelectronic applications.
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