Wyniki wyszukiwania - Biblioteka Nauki

Nowa wersja platformy, zawierająca wyłącznie zasoby pełnotekstowe, jest już dostępna.
Przejdź na https://bibliotekanauki.pl

Ograniczanie wyników

2 Materials Science Poland

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Sortuj według:

Ogranicz wyniki do:

How to make GaMnAs with high ferromagnetic phase transition temperature?

100%

Sadowski J. , Domagała J. Z. , Kanski J. , Rodriguez C. H. , Terki F. , Charar S. , Maude D.

Materials Science Poland

2006

tom Vol. 24, No. 3

617--625

We analyze the role of structural defects in GaMnAs and demonstrate how their density can be drastically reduced by in situ post-growth annealing under As capping. Modifications of the magnetic, transport and structural properties of the annealed GaMnAs layers are presented. The main result is that the Curie temperatures are strongly increased relative those of the as-grown layers, from typically 70 - 80 K to 150 - 160 K. The annealed layers exhibit well-ordered smooth surfaces, suitable for further epitaxial overgrowth.

Raman scattering studies of MBE-grown ZnTe nanowires

84%

Szuszkiewicz W. , Morhange J. F. , Dynowska E. , Janik E. , Zaleszczyk W. , Presz A. , Domagała J. Z. , Caliebe W. , Karczewski G. , Wojtowicz T.

tom Vol. 26, No. 4

1054--1059

We report on the first studies of the optical properties of MBE-grown ZnTe nanowires (NWs). The growth of ZnTe NWs was based on the Au-catalyzed vapour–liquid–solid mechanism and was performed on (001), (011), or (111)B-oriented GaAs substrates. Investigated NWs have a zinc-blende structure, the average diameter of about 30 nm, and typical length between 1 and 2 μm. Their growth axes are oriented along <111>-type directions of the substrate. The structural characterization of the NWs was performed by means of X-ray diffraction, using the synchrotron radiation corresponding to the wavelength of CuKα1 radiation W1 beamline at Hasylab DESY). The macro-Raman spectra of either as-grown NWs on GaAs substrate or of NWs removed from substrate and deposited onto Si were collected at temperatures from 15 K to 295 K using Ar+ and Kr+ laser lines. Strong enhancement of ZnTe-related LO-phonon structure was found for an excitation close to the exciton energy. Our studies revealed also the presence of small trigonal Te precipitates, typical of tellurium compounds.