Autor: Knoff, W. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Magnetic and structural studies of GeMnSnTe epitaxial layers
Autorzy:: Grochot, A.
Knoff, W.
Taliashvili, B.
Wołkanowicz, W.
Minikayev, R.
Pieniążek, A.
Łusakowska, E.
Sawicki, M.
Jantsch, W.
Story, T.
Przybylińska, H.
Powiązania:: https://bibliotekanauki.pl/articles/1055147.pdf
Data publikacji:: 2017-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Gw
75.50.Pp
76.50.+g
Opis:: MBE grown Ge_{1-x-y}Mn_xSn_yTe layers with Mn content ranging from 10 to 30% and Sn content ranging from 2 to 5% have been characterized with X-ray diffraction, energy-dispersive X-Ray spectroscopy, atomic force microscopy, SQUID magnetometry, and ferromagnetic resonance. All layers (except the one with the highest Mn and Sn content) were found to be single phase rhombohedral, with the distortion axis perpendicular to the layer surface, and ferromagnetic. Ferromagnetic resonance studies have shown that co-doping with a few percent of tin makes the lattice more rigid and changes considerably the magnetocrystalline anisotropy, from purely uniaxial in GeMnTe to distorted cubic in Ge_{1-x-y}Mn_xSn_yTe at the same Mn content.
Źródło:: Acta Physica Polonica A; 2017, 132, 2; 340-342
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Magnetic Properties of Epitaxial (Ge,Mn)Te Thin Films with Varying Crystal Stoichiometry
Autorzy:: Knoff, W.
Domukhovski, V.
Dybko, K.
Dziawa, P.
Górska, M.
Jakieła, R.
Łusakowska, E.
Taliashvili, B.
Story, T.
Reszka, A.
Anderson, J.
Rotundu, C.
Powiązania:: https://bibliotekanauki.pl/articles/1811940.pdf
Data publikacji:: 2008-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Pp
Opis:: Magnetization of 1 μm thick ferromagnetic IV-VI (Ge, Mn)Te semiconductor layers with 10 at.% of Mn was studied by SQUID magnetometry method up to the magnetic fields of 70 kOe. The layers were grown on BaF₂ (111) substrates by molecular beam epitaxy with varying Te molecular flux, which permitted the control of layer stoichiometry and conducting hole concentration. X-ray diffraction and in situ electron diffraction characterization of layer growth and crystal structure revealed two-dimensional mode of growth and monocrystalline rhombohedral crystal structure of (Ge, Mn)Te layers. Controlling the layer stoichiometry influences the temperature dependence of magnetization with the ferromagnetic Curie temperature varying in $Ge_{0.9}Mn_{0.1}Te$ layers from $T_c$=30 K (low Te flux) to $T_c$=42 K (high Te flux).
Źródło:: Acta Physica Polonica A; 2008, 114, 5; 1159-1165
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 3.

Tytuł:: Epitaxial Growth and Optical Properties of PbTe/CdTe Semiconductor Heterostructures
Autorzy:: Szot, M.
Kowalczyk, L.
Smajek, E.
Domukhovski, V.
Domagała, J.
Łusakowska, E.
Taliashvili, B.
Dziawa, P.
Knoff, W.
Wiater, M.
Wojtowicz, T.
Story, T.
Powiązania:: https://bibliotekanauki.pl/articles/1811996.pdf
Data publikacji:: 2008-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.55.Hx
78.67.De
78.67.Hc
78.67.Pt
Opis:: Growth optimization, optical and structural properties of PbTe/CdTe multilayers grown by molecular beam epitaxy on GaAs (001) as well as on $BaF_2$ (111) substrates is reported. An intense photoluminescence in the mid-infrared region is observed from PbTe quantum wells excited with 1.17 eV pulsed YAG:Nd laser. The energy of the emission peak shows blue shift with decreasing PbTe well width and has a positive temperature coefficient. The influence of thermal annealing on photoluminescence spectra of PbTe/CdTe multilayers grown on $BaF_2$ substrate is discussed.
Źródło:: Acta Physica Polonica A; 2008, 114, 5; 1391-1396
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 4.

Tytuł:: Ferromagnetic Transition in $Ge_{1-x}Mn_{x}Te$ Layers
Autorzy:: Knoff, W.
Domukhovski, V.
Dybko, K.
Dziawa, P.
Jakieła, R.
Łusakowska, E.
Reszka, A.
Świątek, K.
Taliashvili, B.
Story, T.
Szałowski, K.
Balcerzak, T.
Powiązania:: https://bibliotekanauki.pl/articles/1791343.pdf
Data publikacji:: 2009-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Pp
75.30.Et
81.15.Hi
Opis:: Ferromagnetic transition temperature in thin layers of diluted magnetic (semimagnetic) semiconductor $Ge_{1-x}Mn_{x}Te$ was studied experimentally by SQUID magnetometry method and analyzed theoretically for a model Ising-type diluted magnetic system with Ruderman-Kittel-Kasuya-Yosida indirect exchange interaction. The key features of the experimentally observed dependence of the Curie temperature on Mn content (x ≤ 0.12) and conducting hole concentration p = (1-10) × $10^{21} cm^{-3}$ were reproduced theoretically for realistic valence band and crystal lattice parameters of p-$Ge_{1-x}Mn_{x}Te$ taking into account short carrier mean free path encountered in this material and Ruderman-Kittel-Kasuya-Yosida mechanism with both delta-like and diffused character of spatial dependence of the exchange coupling between magnetic ions and free carriers.
Źródło:: Acta Physica Polonica A; 2009, 116, 5; 904-906
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

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