Under the project
Magnetic, optical and dielectric properties of crystalline and
amorphous systems there is a group in
Vinca Institute working on the subject Diluted Magnetic
Semiconductors in the bulk and nano form.
Semiconducting and magnetic properties of AII1-xMnxBVI
materials (AII= Zn, Cd, Hg, BVI= S, Se, Te, M= Mn, Fe) are
investigated. Emphasis is put on the studies of exchange interaction
between magnetic ions in the wide-gap semiconductors like Zn1-xMnxTe,
and between free carriers and magnetic ions in the narrow-gap
materials as Hg1-xMnxTe and Hg1-xMnxSe.
Influence of these exchange interactions on the relaxation time of
the magnetic ion moments are examined. In Fe-based diluted magnetic
semiconductors like Zn1-xFexSe, Zn1-xFexS
and Cd1-xFexSe
the possible origin of temperature dependent magnetic susceptibility
at low temperatures have been studied within a cluster model.
Diluted magnetic semiconductors of A(II)MnB(VI) type in the form
of nanostructures are also being studied. This programme includes
synthesis and characterization of the nanocrystalline materials,
then studies of their magnetic and optical properties. Cd1‑xMnxS
quantum dots (QDs) of average size 4.5 nm have been synthesized
in our Laboratory using aqueous solution precipitation. The characterization of these
materials is in progress.
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