Optical properties of magnetoexcitons in double quantum dots

Here we investigate the influence of a constant magnetic field on the energy levels and optical properties of excitons in a double quantum disk (quantum molecule). Taking into account the cylindrical symmetry of the double disk we calculate the wave functions and excitonic energies when the external constant magnetic field is applied along the symmetry axis. Having the eigenfunctions and eigenvalues and using the long-wave approximation we can compute all the optical functions. The double quantum dot is considered as one system rather than two interacting dots separated by narrow barrier. The screened Coulomb interaction between an electron and a hole is assumed. Since in the given structure the separation of the relative- and center-of-mass motion of the electron and the hole is not possible, we use an approach where the six-dimensional eigenvalue problem is transformed into the equivalent eigenvalue problem given by the system of the coupled two-dimensional second order differential equations. The so obtained differential equations are solved numerically. As an example, we give detailed results for a InP/InGaP double quantum dot. Satisfactory agreement with the available experimental data is obtained

Optical properties of Rydberg excitons in Cu2_2O based superlattices

Combining the microscopic calculation of superlattice minibands and the macroscopic real density matrix approach one can obtain electric susceptibilities of the superlattice system irradiated by an electromagnetical wave. It is shown how to compute the dispersion relation, excitonic resonances positions and susceptibility of Cu$_2$O/MgO based superlattice (SL), when Rydberg Exciton-Polaritons appear, including the effect of the coherence between the electron-hole pair and the electromagnetic field and the polaritonic effect. Using the Kronig-Penney model for computing miniband SL parameters the analytical expressions for optical functions are obtained and the numerical calculations for Cu$_2$O/MgO SL are performed.Comment: 10 pages, 9 figure

Prevalence of Impaired Hearing and Vision in Patients with Vitiligo

Vitiligo is a common dermatosis occurring witha frequency of about 0.2-4.0% in world population. Themain skin symptom of disease are white patches appearingas a result of destruction or dysfunction of pigment cells(melanocytes). Melanocytes are localized not only in epidermisand bulge region of hair follicle, but also in inner earand eyeball structures, and therefore vitiligo may coexistswith auditory and visual disorders. The most frequent auditoryand visual disturbances occurring in vitiligo patientsare discussed in this article