Joanna Papierska

Giant Spin Splitting in Optically Active ZnMnTe/ZnMgTe Core/Shell Nanowires

An enhancement of the Zeeman splitting as a result of the incorporation of paramagnetic Mn ions in ZnMnTe/ZnMgTe core/shell nanowires is reported. The studied structures are grown by gold-catalyst assisted molecular beam epitaxy. The near band edge emission of these structures, conspicuously absent in the case of uncoated ZnMnTe nanowires, is activated by the presence of ZnMgTe coating. Giant Zeeman splitting of this emission is studied in ensembles of nanowires with various average Mn concentrations of the order of a few percent, as well as in individual nanowires. Thus, we show convincingly that a strong spin sp-d coupling is indeed present in these structures.

Modification of Emission Properties of ZnO Layers due to Plasmonic Near-Field Coupling to Ag Nanoislands.

A simple fabrication method of silver (Ag) nanoislands on ZnO films is presented. Continuous wave and time-resolved photoluminescence and transmission are employed to investigate modifications of visible and UV emissions of ZnO brought about by coupling to localized surface plasmons residing on Ag nanoislands. The size of the nanoislands, determining their absorption and scattering efficiencies, is found to be an important factor governing plasmonic modification of optical response of ZnO films. The presence of the Ag nanoislands of appropriate dimensions causes a strong (threefold) increase in emission intensity and up to 1.5 times faster recombination. The experimental results are successfully described by model calculations within the Mie theory.

Fe dopant in ZnO: 2+ versus 3+ valency and ion-carrier s,p-d exchange interaction

Dopants of transition metal ions in II-VI semiconductors exhibit native 2+ valency. Despite this, 3+ or mixed 3+/2+ valency of iron ions in ZnO was reported previously. Several contradictory mechanisms have been put forward for explanation of this fact so far. Here we analyze Fe valency in ZnO by complementary theoretical and experimental studies. Our calculations within the generalized gradient approximation (GGA+

Synthesis and magnetooptic characterization of Cu-doped ZnO/MgO and ZnO/oleic acid core/shell nanoparticles

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Relation between exciton splittings, magnetic circular dichroism, and magnetization in wurtzite Ga_(1-x)Fe_xN

indicate that the Fe ion is a relatively shallow donor. Its stable charge state is

Exciton dynamics in individual semimagnetic (Zn,Mn)Te/(Zn,Mg)Te nanowires

{\mathrm{Fe}}^{2+}

Raman measurements of temperature dependencies of phonons in LiMnPO4

in ideal ZnO, however, the high energy of the (+/0) transition level enhances the compensation of

Efficient Emission from InAlGaAs Single Quantum Dots with Low Lattice Misfit and AlGaAs Indirect Bandgap Barrier

{\mathrm{Fe}}^{2+}

Strong sp–d exchange coupling in ZnMnTe/ZnMgTe core/shell nanowires

to

Optical Properties of CdTe QDs in Proximity to a Surface

{\mathrm{Fe}}^{3+}