Luminescence Emission in Borotellurite Glass Containing Manganese Nanoparticles Doped Eu3+ Ions

A series of europium doped magnesium borotellurite glasses embedded with manganese nanoparticles (Mn3O4 NPs) of composition (59-x)TeO2-30B2O3-10MgO-x1Eu2O3-1Mn3O4 with 0.5 ≤ x ≤ 1.5 mol % are prepared using melt quenching technique. The existence of broad hump in X-ray diffraction (XRD) pattern verifies the amorphous nature of glasses. The presence of Mn3O4 NPs with average diameter of ~11 nm and (1 0 3) lattice plane having 0.276 nm spacing in the glass matrix is confirmed by high resolution transmission electron microscope (HRTEM) image. The glass samples are excited under 390 nm excitation wavelength and the emission spectra are found to consist of four emission peaks centred at 587 nm, 610 nm, 651 nm and 700 nm assigned to the transition from 5D0 →7FJ (J = 1, 2, 3, 4) states. The schematic energy level diagram is proposed. All results will be discussed with respect to the composition of Eu3+ ion.

Luminescence Studies of Erbium Doped Sodium Magnesium Boro-Tellurite Glass

The optical behaviour of Er3+ (1.0 – 2.0 mol %) doped B2O3-TeO2- Na2O-MgO glasses synthesized by conventional melt-quenching technique was studied through luminescence measurements. The X-ray diffraction (XRD) pattern confirms the amorphous nature of the glasses without the existence of any sharp peak. The emission spectra at 378 nm excitation displayed three emission peaks corresponding to 2H11/2-4I15/2, 4S3/2-4I15/2 and4I9/2-4I15/2 transitions. Hence, a schematic energy level diagram was proposed. The luminescence properties of the prepared glasses was found to be strongly affected by varying the concentration of Er3+ ions.

Band Structure and Electronic Excitations in Cdl-xMnxTe

We have performed spin-polarized, self-consistent local spin density total energy and band structure calculations for the prototype semimagnetic semiconductor alloy Cd1-xMnxTe. Based on the calculated band structures and taking into account the many body effects of localized states, we propose a schematic energy level diagram to interpret the d→d*, p→d, and photoemission transitions in Cd1-xMnxTe.