Electronic and optical properties of semiconductor nanostructures

Abstract

The single particle spectrum of a charged particle in a nanometric ellipsoidal quantum dot is calculated taking also into account the surface polarization effects. Furthermore the optical properties of the absorption coefficient also depending on the light polarisation are discussed and compared with the experimental data

On the Optical Stark Effect of Excitons in InGaAs Prolate Ellipsoidal Quantum Dots

“…We consider a prolate ellipsoidal quantum dot with rotational symmetry around the z axis, with a and c are its semi-axes along the xOy plane and stay in the z-direction, respectively, in which x, y, and z are the coordinates in Cartesian coordinate system with its origin at the ellipsoidal symmetry center (Figure 1). Simply put, we assume that prolate ellipsoidal quantum dot is set under the effect of an infinite potential of the form [25][26][27][28][29]…”

Magnetoabsorption coefficient of donor impurities in CdS quantum dot

“…In the case of an on-center donor investigated previously [15,20], the absorption coefficient is independent of the direction of the polarization of the light. In this case an unpolarised isotropic radiation was considered.…”

“…(9) and (11) was replaced by a Lorentzian with a width equal to 1 meV [15]. This may be understood as a numerical artifact to simulate the broadening process, which has not been introduced in the theoretical derivation of Eqs.…”

“…They have found that, because of the quantum dot confinement the infrared magnetoabsorption strongly depends on the position of the impurity in the dot. Iadonisi et al [15] have discussed the electronic and optical properties of semiconductor nanostructures. While a great part of these studies were concerned with the absorption coefficient associated with transition between shallow-donor states, the study of the absorption coefficient associated with the transition between the donor impurity band and the conduction subband are much less investigated.…”

Quantum Beat of Excitons in the Prolate Ellipsoidal Quantum Dots

“…This suggests that specially shaped QDs like ellipsoidal ones can possess interestingly different optical properties. In ellipsoidal QDs, the quantized energy levels of particles are highly dependent on structural parameters [19][20][21][22][23]. Therefore, the optical properties in these quantum dot structures are said to be easily modifiable by these structural parameters.…”