Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Nanomaterials

Electromagnetically Induced Transparency in a GaAs Coupled Quantum Dot-Ring

R. V. H. Hahn, A. S. Giraldo-Neira, Juan Alejandro Vinasco, John A. Gil-Corrales, Alvaro Luis Morales, C.A. Duque

Published Sep 22, 2025• 3 citations
Publisher

Abstract

In this work, the ground and low-lying excited states in a GaAs coupled quantum dot-ring embedded in an AlGaAs cylindrical matrix are computed under the assumption of a finite confinement potential and an axisymmetric model by means of the finite element method and the effective mass approximation. The electron energy levels are studied as functions of the intensity of externally applied electric and magnetic fields. Electromagnetically induced transparency in the ladder configuration and linear optical absorption coefficient are calculated thereupon. Our results suggest that magnetic fields are more suitable than electric fields for controlling the optical properties of this nanostructure. Also, we found that the system's response, however, exhibits a striking asymmetry: while the electromagnetically induced transparency is unexpectedly quenched under positive electric fields due to vanishing dipole transition matrix elements, this limitation is completely overcome by a magnetic field. Its application not only restores optical transparency across the full range of electric field values but also drives substantially larger energy level shifts and clear Aharonov-Bohm oscillations, making it a far more robust tool for controlling the optical properties of confined electrons in dot-ring coupled heterostructures.

DOI
10.3390/nano15181455

Related papers

Optical Properties of Cylindrical Quantum Dots with Hyperbolic-Type Axial Potential under Applied Electric Field

Carlos Alberto Duque Echeverri, Esin KASAPOĞLU, Melike Behiye Yücel +2 more

ABSTRACT: In this paper, we have researched the electronic and optical properties of cylindrical quantum dot structures by selecting four different hyperbolic-type potentials in the axial direction under an axially-applied electric field. We have considered a position-dependent effective mass model in which both the smooth variation of the effective mass in the axial direction adjusted to the way the confining potentials change and its abrupt change in the radial direction have been considered in solving the eigenvalue differential equation. The calculations of the eigenvalue equation have been implemented considering both the Dirichlet conditions (zero flux) and the open boundary conditions (non-zero flux) in the planes perpendicular to the direction of the applied electric field, which guarantees the validity of the results presented in this study for quasi-steady states with extremely high lifetimes. We have used the diagonalization method combined with the finite element method to find the eigenvalues and eigenfunction of the confined electron in the cylindrical quantum dots. The numerical strategies that have been used for the solution of the differential equations allowed us to overcome the multiple problems that the boundary conditions present in the region of intersection of the flat and cylindrical faces that form the boundary of the heterostructure. To calculate the linear and third-order nonlinear optical absorption coefficients and relative changes in the refractive index, a two-level approach in the density matrix expansion is used. Our results show that the electronic and, therefore, optical properties of the structures focused on can be adjusted to obtain a suitable response for specific studies or goals by changing structural parameters such as the widths and depths of the potentials in the axial direction, as well as the electric field intensity.

•Jan 1, 2022•0 citations

Optical Properties of Cylindrical Quantum Dots with Hyperbolic-Type Axial Potential under Applied Electric Field

Esin KASAPOĞLU, Melike Behiye Yücel, S. Şakiroğlu +2 more

In this paper, we have researched the electronic and optical properties of cylindrical quantum dot structures by selecting four different hyperbolic-type potentials in the axial direction under an axially-applied electric field. We have considered a position-dependent effective mass model in which both the smooth variation of the effective mass in the axial direction adjusted to the way the confining potentials change and its abrupt change in the radial direction have been considered in solving the eigenvalue differential equation. The calculations of the eigenvalue equation have been implemented considering both the Dirichlet conditions (zero flux) and the open boundary conditions (non-zero flux) in the planes perpendicular to the direction of the applied electric field, which guarantees the validity of the results presented in this study for quasi-steady states with extremely high lifetimes. We have used the diagonalization method combined with the finite element method to find the eigenvalues and eigenfunction of the confined electron in the cylindrical quantum dots. The numerical strategies that have been used for the solution of the differential equations allowed us to overcome the multiple problems that the boundary conditions present in the region of intersection of the flat and cylindrical faces that form the boundary of the heterostructure. To calculate the linear and third-order nonlinear optical absorption coefficients and relative changes in the refractive index, a two-level approach in the density matrix expansion is used. Our results show that the electronic and, therefore, optical properties of the structures focused on can be adjusted to obtain a suitable response for specific studies or goals by changing structural parameters such as the widths and depths of the potentials in the axial direction, as well as the electric field intensity.

Nanomaterials•Sep 27, 2022•25 citations

Tuning Electromagnetically Induced Transparency in a Double GaAs/AlGaAs Quantum Well with Modulated Doping

C. A. Dagua-Conda, John A. Gil-Corrales, R. V. H. Hahn +4 more

Including an n-doped layer in asymmetric double quantum wells restricts confined carriers into V-shaped potential profiles, forming discrete conduction subbands and enabling intersubband transitions. Most studies on doped semiconductor heterostructures focus on how external fields and structural parameters dictate optical absorption. However, electromagnetically induced transparency remains largely unexplored. Here, we show that the effect of an n-doped layer GaAs/AlxGa1−xAs in an asymmetric double quantum well system is quite sensitive to the width and position of the doped layer. By self-consistently solving the Poisson and Schrödinger’s equations, we determine the electronic structure using the finite element method within the effective mass approximation. We found that the characteristics of the n-doped layer can modulate the resonance frequencies involved in the electromagnetically induced transparency phenomenon. Our results demonstrate that an n-doped layer can control the electromagnetically induced transparency effect, potentially enhancing its applications in optoelectronic devices.

Crystals•Mar 6, 2025•10 citations

Optical properties of a single quantum well under electric and tilted magnetic fields

R. Özbakır

In this study, the effects of electric and tilted magnetic fields on changes in the total absorption coefficient and the refractive index, including the linear and third-order nonlinear terms for transition between the ground and first excited level of an electron confined within the GaAs/GaAlAs quantum well, have been investigated. Furthermore, the effects of the magnetic field direction (i.e., different tilt angles) and the well parameters as well as the electric field strength on the optical properties are taken into consideration. The energy levels and wave functions of the system are calculated by using the effective mass approximation and the compact density-matrix approach is used for optical transitions. The obtained results show that the optical properties of the system are sensitive to the applied external fields and well dimensions.

Canadian Journal of Physics•Jan 11, 2018•3 citations

Optical properties in GaAs/AlGaAs semiparabolic quantum wells by the finite difference method: Combined effects of electric field and magnetic field

Ruyu Yan, Jian Tang, Zhihai Zhang +1 more

In the present work, the optical properties of GaAs/AlGaAs semiparabolic quantum wells (QWs) are studied under the effect of applied electric field and magnetic field by using the compact-density-matrix method. The energy eigenvalues and their corresponding eigenfunctions of the system are calculated by using the differential method. Simultaneously, the nonlinear optical rectification (OR) and optical absorption coefficients (OACs) are investigated, which are modulated by the applied electric field and magnetic field. It is found that the position and the magnitude of the resonant peaks of the nonlinear OR and OACs can depend strongly on the applied electric field, magnetic field and confined potential frequencies. This gives a new way to control the device applications based on the intersubband transitions of electrons in this system.

International Journal of Modern Physics B•Apr 2, 2018•21 citations

Slow light control with electric fields in vertically coupled InGaAs/GaAs quantum dots

Chun-Hua Yuan, Ka‐Di Zhu, Yiwen Jiang

Tunneling-induced transparency in vertically coupled InGaAs/GaAs quantum dots using tunneling instead of pump laser, analogous to electromagnetically induced transparency in atomic systems, is studied. The interdot quantum coupling strength is tuned by static electric fields. The group velocity slow-down factor is theoretically analyzed as a function of electron tunneling at different broadened linewidths. For parameters appropriate to a 100 Gbits/s optical network, group velocities as low as 850 m/s are calculated. The scheme is expected to be useful to construct a variable semiconductor optical buffer based on electromagnetically induced transparency in vertically coupled InGaAs/GaAs quantum dots controlled by electric fields.

Journal of Applied Physics•Jul 15, 2007•18 citations
In this work, the ground and low-lying excited states in a GaAs coupled quantum dot-ring embedded in an AlGaAs cylindrical matrix are computed under the assumption of a finite confinement potential and an axisymmetric model by means of the finite element method and the effective mass approximation. The electron energy levels are studied as functions of the intensity of externally applied electric and magnetic fields. Electromagnetically induced transparency in the ladder configuration and linear optical absorption coefficient are calculated thereupon. Our results suggest that magnetic fields are more suitable than electric fields for controlling the optical properties of this nanostructure. Also, we found that the system's response, however, exhibits a striking asymmetry: while the electromagnetically induced transparency is unexpectedly quenched under positive electric fields due to vanishing dipole transition matrix elements, this limitation is completely overcome by a magnetic field. Its application not only restores optical transparency across the full range of electric field values but also drives substantially larger energy level shifts and clear Aharonov-Bohm oscillations, making it a far more robust tool for controlling the optical properties of confined electrons in dot-ring coupled heterostructures.
ABSTRACT: In this paper, we have researched the electronic and optical properties of cylindrical quantum dot structures by selecting four different hyperbolic-type potentials in the axial direction under an axially-applied electric field. We have considered a position-dependent effective mass model in which both the smooth variation of the effective mass in the axial direction adjusted to the way the confining potentials change and its abrupt change in the radial direction have been considered in solving the eigenvalue differential equation. The calculations of the eigenvalue equation have been implemented considering both the Dirichlet conditions (zero flux) and the open boundary conditions (non-zero flux) in the planes perpendicular to the direction of the applied electric field, which guarantees the validity of the results presented in this study for quasi-steady states with extremely high lifetimes. We have used the diagonalization method combined with the finite element method to find the eigenvalues and eigenfunction of the confined electron in the cylindrical quantum dots. The numerical strategies that have been used for the solution of the differential equations allowed us to overcome the multiple problems that the boundary conditions present in the region of intersection of the flat and cylindrical faces that form the boundary of the heterostructure. To calculate the linear and third-order nonlinear optical absorption coefficients and relative changes in the refractive index, a two-level approach in the density matrix expansion is used. Our results show that the electronic and, therefore, optical properties of the structures focused on can be adjusted to obtain a suitable response for specific studies or goals by changing structural parameters such as the widths and depths of the potentials in the axial direction, as well as the electric field intensity.
In this paper, we have researched the electronic and optical properties of cylindrical quantum dot structures by selecting four different hyperbolic-type potentials in the axial direction under an axially-applied electric field. We have considered a position-dependent effective mass model in which both the smooth variation of the effective mass in the axial direction adjusted to the way the confining potentials change and its abrupt change in the radial direction have been considered in solving the eigenvalue differential equation. The calculations of the eigenvalue equation have been implemented considering both the Dirichlet conditions (zero flux) and the open boundary conditions (non-zero flux) in the planes perpendicular to the direction of the applied electric field, which guarantees the validity of the results presented in this study for quasi-steady states with extremely high lifetimes. We have used the diagonalization method combined with the finite element method to find the eigenvalues and eigenfunction of the confined electron in the cylindrical quantum dots. The numerical strategies that have been used for the solution of the differential equations allowed us to overcome the multiple problems that the boundary conditions present in the region of intersection of the flat and cylindrical faces that form the boundary of the heterostructure. To calculate the linear and third-order nonlinear optical absorption coefficients and relative changes in the refractive index, a two-level approach in the density matrix expansion is used. Our results show that the electronic and, therefore, optical properties of the structures focused on can be adjusted to obtain a suitable response for specific studies or goals by changing structural parameters such as the widths and depths of the potentials in the axial direction, as well as the electric field intensity.
Including an n-doped layer in asymmetric double quantum wells restricts confined carriers into V-shaped potential profiles, forming discrete conduction subbands and enabling intersubband transitions. Most studies on doped semiconductor heterostructures focus on how external fields and structural parameters dictate optical absorption. However, electromagnetically induced transparency remains largely unexplored. Here, we show that the effect of an n-doped layer GaAs/AlxGa1−xAs in an asymmetric double quantum well system is quite sensitive to the width and position of the doped layer. By self-consistently solving the Poisson and Schrödinger’s equations, we determine the electronic structure using the finite element method within the effective mass approximation. We found that the characteristics of the n-doped layer can modulate the resonance frequencies involved in the electromagnetically induced transparency phenomenon. Our results demonstrate that an n-doped layer can control the electromagnetically induced transparency effect, potentially enhancing its applications in optoelectronic devices.
In this study, the effects of electric and tilted magnetic fields on changes in the total absorption coefficient and the refractive index, including the linear and third-order nonlinear terms for transition between the ground and first excited level of an electron confined within the GaAs/GaAlAs quantum well, have been investigated. Furthermore, the effects of the magnetic field direction (i.e., different tilt angles) and the well parameters as well as the electric field strength on the optical properties are taken into consideration. The energy levels and wave functions of the system are calculated by using the effective mass approximation and the compact density-matrix approach is used for optical transitions. The obtained results show that the optical properties of the system are sensitive to the applied external fields and well dimensions.
In the present work, the optical properties of GaAs/AlGaAs semiparabolic quantum wells (QWs) are studied under the effect of applied electric field and magnetic field by using the compact-density-matrix method. The energy eigenvalues and their corresponding eigenfunctions of the system are calculated by using the differential method. Simultaneously, the nonlinear optical rectification (OR) and optical absorption coefficients (OACs) are investigated, which are modulated by the applied electric field and magnetic field. It is found that the position and the magnitude of the resonant peaks of the nonlinear OR and OACs can depend strongly on the applied electric field, magnetic field and confined potential frequencies. This gives a new way to control the device applications based on the intersubband transitions of electrons in this system.
Tunneling-induced transparency in vertically coupled InGaAs/GaAs quantum dots using tunneling instead of pump laser, analogous to electromagnetically induced transparency in atomic systems, is studied. The interdot quantum coupling strength is tuned by static electric fields. The group velocity slow-down factor is theoretically analyzed as a function of electron tunneling at different broadened linewidths. For parameters appropriate to a 100 Gbits/s optical network, group velocities as low as 850 m/s are calculated. The scheme is expected to be useful to construct a variable semiconductor optical buffer based on electromagnetically induced transparency in vertically coupled InGaAs/GaAs quantum dots controlled by electric fields.