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Technology Profile
New Anti – Stokes Luminophors and Laser Mediums
on the Base of II-III 2 - VI 4 Typed Wide-Band Chalcogenide
Semiconductors Doped by Rare-Earth Elements
Description
Traditional investigations, synthesis and use of anti –
Stokes luminophors (ASL) have an objective to visualize
IR-radiation, i.e. IR-signal conversion into visible band
(0.38÷0.76mkm). Recently there have been created systems
of length fiber optic communication lines where data
carrier is the radiation with wavelength about 1.55 mkm.
There have been developed lasers on the base of erbium
glasses with wavelength of generation 1.54÷1.65 mkm.
Therefore activation of wide-band semiconductive compounds
EuGa 2S 4 and YbGa 2S 4 by 4f-elements, study of impurity
state and behavior is one of the central issues of
physics and material science of semiconductors as a
whole.
Nowadays complex rare – earth compounds of MIM II
2 X4VI (MI -Eu, Yl,Sm; MII-Ga,In; X VI
4 - S,Se) – typed take a special
place among wide - band semiconductors.
MIM II
2 X4VI - typed crystals have been crystallized in rhombic
singony, they are high – resistance (105 ÷10IIOhm/cm), wide-band (~4.4eV) semiconductors and show particularly
pronounced luminescent and photoconductive properties.
In according with above- mentioned it is of interest spectroscopic
investigation of 4f-elements in Eu (Yb) Ga2S4 crystals.
There has been developed technology of II-III2 - IV2 (II-Eu,
Yb,Sm,Ca, Sr,Ba; III-Ga,Al;VI-S,Se,O) - typed semiconductors
activated by rare-earth ions.
Innovative Aspects and Main Advantages
Production of effective devices for visualization and illumination,
being able to compete with traditional systems requires
to manufacture luminophors with specific properties.
This necessity promotes development of new materials and
optimization of existing luminophors. İn this aspect perspective
ones are ternary alkali-earth chalcogenide semiconductors
of II-III 2 - IV 2 (II-Eu, Yb,Sm,Ca, Sr,Ba;
III-Ga,Al;VI-S,Se,O) – typed activated by rare-earth ions.
One of the qualities of ternary compounds comparing
favourably with binary one as regards applied use is the resistance
to hydrolysis and good implantation of rare-earth
ions into crystal lattice. High linearity of cathode luminescence
at high densities of current makes them suitable for
use as a luminophor in TV and field ionization displays. Se-
Contact Details
Institute of Physics
Contact person: Tagiev Oktay Bahadur
Address: 33, H. Javid Avenue
AZ1143, Baku, Azerbaijan
lection of corresponding sensitizers and activators one can
change efficiency of conversion of various kinds of energy
into light one and luminescence colors of these compounds.
Areas of Application
Systems of fiber optic communication lines, lasers with
wavelength of generation 1.54-1/65mkm, night vision
equipments.
Stage of Development
Development phase - laboratory tested.
Fig.1 The diagram of light emitting diode with phosphide we.
Fig.2. Three-color combination wed in light emitting diode.
Tel: (994 12) 439 6795
Fax: (994 12) 447 0456
E-mail: oktay58@mail.ru
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