Europium doping of cadmium selenide (CdSe) quantum dots via rapid microwave synthesis for optoelectronic applications

UV-Vis spectroscopy and PL data show that structural incorporation of Eu3+ has an effect on the optical properties of CdSe QDs via energy transfer from host to dopant. This allows for QDs with tunable optical properties via numerous pathways.

Особенности поведения ионов Mn-=SUP=-2+-=/SUP=- в 3D-дираковском полуметалле alpha-Cd-=SUB=-3-=/SUB=-As-=SUB=-2-=/SUB=- по данным ЭПР

The behavior of the manganese impurity in the 3D Dirac semimetal Cd3As2 has been studied by EPR and electromagnetic measurements. It was found that, in contrast to doping with europium, doping with manganese, as well as with iron, does not lead to a change in the sign of the magnetoresistance, which is almost completely suppressed at high manganese concentrations. In this case, a change in the type of the influence of the magnetic field on the contact potential is manifested. The g-factors measured in EPR coincide with the g-factor of a free electron at all temperatures, which, taking into account the fluctuation behavior of the EPR linewidth and the reduced magnetic moment on Mn2 +, indicates the formation of short-lived bound states of the Mn2 + ion and conduction electrons - antiferromagnetic polarons.

Europium Doping Impact on the Properties of MBE Grown Bi2Te3 Thin Film

The impact of europium doping on the electronic and structural properties of the topological insulator Bi2Te3 is studied in this paper. The crystallographic structure studied by electron diffraction and transmission microscopy confirms that grown by Molecular Beam Epitaxy (MBE) system film with the Eu content of about 3% has a trigonal structure with relatively large monocrystalline grains. The X-ray photoemission spectroscopy indicates that europium in Bi2Te3 matrix remains divalent and substitutes bismuth in a Bi2Te3 matrix. An exceptional ratio of the photoemission 4d multiplet components in Eu doped film was observed. However, some spatial inhomogeneity at the nanometer scale is revealed. Firstly, local conductivity measurements indicate that the surface conductivity is inhomogeneous and is correlated with a topographic image revealing possible coexistence of conducting surface states with insulating regions. Secondly, Time of Flight Secondary Ion Mass Spectrometry (TOF-SIMS) depth-profiling also shows partial chemical segregation. Such in-depth inhomogeneity has an impact on the lattice dynamics (phonon lifetime) evaluated by femtosecond spectroscopy. This unprecedented set of experimental investigations provides important insights for optimizing the process of growth of high-quality Eu-doped thin films of a Bi2Te3 topological insulator. Understanding such complex behaviors at the nanoscale level is a necessary step before considering topological insulator thin films as a component of innovative devices.

Adverse Effect of Europium Doping on Magneto-Optical Properties of Cr2O3

The article describes in detail the effect of doping Europium (Eu) on magnetic and optical properties of Cr2O3. Undoped and Eu (1–5 mol%) doped Cr2O3 samples were synthesized using solid state synthesis method. The structural, magnetic and optical properties of undoped and Europium (Eu) doped chromium oxide powder were studied by X-ray diffractometer (XRD), vibrating sample magnetometer (VSM) and photoluminescence (PL) measurements. The X-ray diffraction pattern confirms the polycrystalline nature of undoped and Europium (Eu) doped chromium oxide powder. The magnetic measurements revealed decline in magnetism with increasing Eu concentration. With increasing Eu concentration, the visible luminescence of Cr2O3 improved. The study highlighted that Eu as a dopant is not suitable for improving the magnetic properties of Cr2O3.