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For your information:
A study carried out by teams from the Electronics,
Microelectronics and Nanotechnology Institute of the CNRS (IEMN, Villeneuve
d'Ascq, France) and the Debye Institute in Utrecht (Netherlands) recently
demonstrated that semiconductor nanostructures behaved like artificial
atoms.
Researchers have synthesized ZnO nanocrystals
(zinc oxide) using electrochemical techniques and then charged them with
one to ten electrons under controlled conditions, corresponding to the
beginning of the periodic table, from hydrogen to neon.
They also showed that as a result of their size, these nanocrystals are
characterized by discrete electron shells, identical to those of atoms.
Optical absorption measurements and theoretical calculations bear proof
that the electrons are distributed by shell and follow the same transition
rules as in atoms. The energy of the artificial atom levels can be adjusted
by changing semiconductors or by changing the size of the semiconductor
itself.
Deposited in thin layers, these nanocrystals can form new materials whose
electrical conductivity can be modified, for example. A first step in
this direction has been taken in Utrecht.
Reference: Physical Review Letters
– March 7, 2003
Researcher contact:
Christophe Delerue
Tel: +33 3 20 30 40 53
E-mail: Christophe.Delerue@isen.fr
Press contact
Muriel Ilous
Tel: +33 1 44 96 43 09
E-mail: muriel.ilous@cnrs-dir.fr
Contact: Physics and Mathematics
Department
Frédérique Laubenheimer
Tel: +33 1 44 96 42 63
E-mail: frederique.laubenheimer@cnrs-dir.fr
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