10 research outputs found
Introduction to the Physics of Diluted Magnetic Semiconductors
The book deals with diluted magnetic semiconductors, a class of materials important to the emerging field of spintronics. In these materials semiconducting properties, both transport and optical, are influenced by the presence of magnetic ions. It concentrates on basic physical mechanisms (e.g. carrier-ion and ion-ion interactions) and resulting phenomena (e.g. magnetic polaron formation and spin relaxation). Introduction to the Physics of Diluted Magnetic Semiconductors is addressed to graduate-level and doctoral students and young researchers entering the field. The authors have been actively involved in the creation of this branch of semiconductor physics
Optical properties of a semimagnetic quantum well in a proximity of a superconducting film
We consider, via numerical calculations, a hybrid structure made of a semimagnetic Cd1-xMnxTe quantum well deposited in a close proximity to superconducting niobium film. We simulate photoluminescence and the Faraday rotation spectra, modified by the presence of vortices in this type II superconductor. The magnitude of the evaluated effects is small - the vortex induced spectral line shape variation is of the order of 1% at 1 K and 0.1% at 3 K and is expected to occur mainly in the field range between 0.03 T and 0.05 T
Spin Splitting Anisotropy in Single Diluted Magnetic Nanowire Heterostructures
We study the impact of the nanowire
shape anisotropy on the spin splitting of excitonic photoluminescence.
The experiments are performed on individual ZnMnTe/ZnMgTe core/shell
nanowires as well as on ZnTe/ZnMgTe core/shell nanowires containing
optically active magnetic CdMnTe insertions. When the magnetic field
is oriented parallel to the nanowire axis, the spin splitting is several
times larger than for the perpendicular field. We interpret this pronounced
anisotropy as an effect of mixing of valence band states arising from
the strain present in the core/shell geometry. This interpretation
is further supported by theoretical calculations which allow to reproduce
experimental results
Giant Zeeman splitting in nucleation-controlled doped CdSe:Mn2+ quantum nanoribbons
Doping of semiconductor nanocrystals by transition-metal ions has attracted tremendous attention owing to their nanoscale spintronic applications. Such doping is, however, difficult to achieve in low-dimensional strongly quantum confined nanostructures by conventional growth procedures. Here we demonstrate that the incorporation of manganese ions up to 10% into CdSe quantum nanoribbons can be readily achieved by a nucleation-controlled doping process. The cation-exchange reaction of (CdSe) 13 clusters with Mn 2+ ions governs the Mn 2+ incorporation during the nucleation stage. This highly efficient Mn 2+ doping of the CdSe quantum nanoribbons results in giant exciton Zeeman splitting with an effective g-factor of 600, the largest value seen so far in diluted magnetic semiconductor nanocrystals. Furthermore, the sign of the s-d exchange is inverted to negative owing to the exceptionally strong quantum confinement in our nanoribbons. The nucleation-controlled doping strategy demonstrated here thus opens the possibility of doping various strongly quantum confined nanocrystals for diverse applications.close6