info:eu-repo/semantics/article
Optical Properties in a ZnS/CdS/ZnS Core/Shell/Shell Spherical Quantum Dot: Electric and Magnetic Field and Donor Impurity Effects
Registro en:
Toscano-Negrette RG, León-González JC, Vinasco JA, Morales AL, Koc F, Kavruk AE, Sahin M, Mora-Ramos ME, Sierra-Ortega J, Martínez-Orozco JC, Restrepo RL, Duque CA. Optical Properties in a ZnS/CdS/ZnS Core/Shell/Shell Spherical Quantum Dot: Electric and Magnetic Field and Donor Impurity Effects. Nanomaterials (Basel). 2023 Jan 29;13(3):550. doi: 10.3390/nano13030550.
10.3390/nano13030550
2079-4991
Autor
Toscano Negrette, Rafael Guillermo
León González, José Carlos
Vinasco Suárez, Juan Alejandro
Morales Aramburo, Álvaro Luis
Koc, Fatih
Kavruk, Ahmet Emre
Sahin, Mehmet
Mora Ramos, Miguel Eduardo
Sierra Ortega, José
Martínez Orozco, Juan Carlos
Restrepo Arango, Ricardo León
Duque Echeverri, Carlos Alberto
Institución
Resumen
ABSTRACT: A theoretical analysis of optical properties in a ZnS/CdS/ZnS core/shell/shell spherical quantum dot was carried out within the effective mass approximation. The corresponding Schrödinger equation was solved using the finite element method via the 2D axis-symmetric module of COMSOL-Multiphysics software. Calculations included variations of internal dot radius, the application of electric and magnetic fields (both oriented along z-direction), as well as the presence of on-center donor impurity. Reported optical properties are the absorption and relative refractive index change coefficients. These quantities are related to transitions between the ground and first excited states, with linearly polarized incident radiation along the z-axis. It is found that transition energy decreases with the growth of internal radius, thus causing the red-shift of resonant peaks. The same happens when the external magnetic field increases. When the strength of applied electric field is increased, the opposite effect is observed, since there is a blue-shift of resonances. However, dipole matrix moments decrease drastically with the increase of the electric field, leading to a reduction in amplitude of optical responses. At the moment impurity effects are activated, a decrease in the value of the energies is noted, significantly affecting the ground state, which is more evident for small internal radius. This is reflected in an increase in transition energies. COL0033319