in order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. to do this we have investigated optical waveguide both with and without optical pumping. the rate of absorption and emission using an array of algaas/gaas quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. by con...

Abstract Different stellar phenomena affect radial velocities (RVs), causing variations large enough to make it difficult identify planet signals from the variability. RV caused by oscillations and granulation can be reduced through some methods, but impact of rotationally modulated magnetic activity on RV, due active regions, is harder correct. New instrumentation promises an improvement in pr...

This study reports for the first time theoretical prediction of structural, electronic, elastic and optical properties cubic BaLiCl3, BaLiBr3, BaLiI3 perovskites. The corresponding well-known BaLiF3 are also theoretically investigated. Density Functional Theory (DFT) using Generalized Gradient Approximation (GGA) was implemented within Quantum Espresso package to investigate results revealed th...

We introduce HP, an implementation of density-functional perturbation theory, designed to compute Hubbard parameters (on-site $U$ and inter-site $V$) in the framework DFT+$U$ DFT+$U$+$V$. The code does not require use computationally expensive supercells traditional linear-response approach; instead, unit cells are used with monochromatic perturbations that significantly reduce computational co...

Aims. We report on ESPRESSO high-resolution transmission spectroscopic observations of two primary transits the highly irradiated, ultra-hot Jupiter-sized planet, WASP-76b. investigated presence several key atomic and molecular features interest that may reveal atmospheric properties planet. Methods. extracted spectra WASP-76b with R ? 140 000 using a procedure allowed us to process full wavele...

the time evaluation of quantum entropy in a four-level double- type atomic system is theoretically investigated. quantum entanglement of the atom and its spontaneous emission fields is then discussed via quantum entropy. it is found that the degree of entanglement can be increased by the quantum interference induced by spontaneous emission. the phase dependence of the atom-field entanglement is...