Temat: 74.72.Dn - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Epitaxially Induced Defects in Sr- and O-doped La$\text{}_{2}$CuO$\text{}_{4}$ Thin Films Grown by MBE: Implications for Transport Properties
Autorzy:: Locquet, J.-P
Williams, E. J.
Powiązania:: https://bibliotekanauki.pl/articles/1964235.pdf
Data publikacji:: 1997-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.72.Nn
74.62.Fj
81.15.Hi
74.72.Dn
Opis:: In this paper, the critical role played by various types of defects and strain relaxation mechanisms in high-T$\text{}_{c}$ thin films is highlighted and illustrated with examples. The defects are essential for providing adequate diffusion channels for oxygen ingress during the cooling step in c-axis thin films. The operation of strain relaxation mechanisms necessitated by the lattice mismatch between film and substrate can impose a compressive or tensile biaxial pressure, which either increases or reduces the critical temperature.
Źródło:: Acta Physica Polonica A; 1997, 92, 1; 69-84
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Anharmonicity and Weak Mode Assignment in La$\text{}_{2-x}$Sr$\text{}_{x}$CuO$\text{}_{4}$, with Oxygen Isotopic Substitution
Autorzy:: Siranidi, E.
Lampakis, D.
Palles, D.
Liarokapis, E.
Conder, K.
Powiązania:: https://bibliotekanauki.pl/articles/2047249.pdf
Data publikacji:: 2007-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.30.-j
31.30.Gs
74.25.Kc
74.72.Dn
Opis:: The oxygen isotope effect on the first- and second-order Raman active modes of high-quality La$\text{}_{2-x}$Sr$\text{}_{x}$Cu$\text{}^{16,18}$O$\text{}_{4}$ (80% substitution $\text{}^{16}$O by $\text{}^{18}$O) polycrystalline compounds with x=0.00, 0.015 was investigated at low temperatures. In the second-order Raman scattering several weak and strong peaks were observed and assigned to oxygen atom vibrations. With the isotopic substitution the apex oxygen mode follows quite well the mass harmonic law at all temperatures studied, while the soft mode is anharmonic in the temperature range of 77-180 K and for higher temperatures its anharmonicity is strongly increased. The temperature dependence of the energy of the soft mode for x=0.0 shows also a modification at≈180 K and an abnormal behaviour at≈280 K, which may be related with the transition to the antiferromagnetic phase.
Źródło:: Acta Physica Polonica A; 2007, 111, 1; 173-177
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 3.

Tytuł:: Strain Relaxation in Thin Films of La$\text{}_{1.85}$Sr$\text{}_{0.15}$CuO$\text{}_{4}$ Grown by Pulsed Laser Deposition
Autorzy:: Zaytseva, I.
Cieplak, M. Z.
Abal'oshev, A.
Berkowski, M.
Domukhovski, V.
Paszkowicz, W.
Shalimov, A.
Powiązania:: https://bibliotekanauki.pl/articles/2047252.pdf
Data publikacji:: 2007-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 68.55.-a
74.62.-c
74.72.Dn
74.78.Bz
74.25.Fy
Opis:: X-ray diffraction, resistivity, and susceptibility measurements are used to examine the effects of film thickness d (from 17 to 250 nm) on the structural and superconducting properties of La$\text{}_{1.85}$Sr$\text{}_{0.15}$CuO$\text{}_{4}$ films grown by pulsed laser deposition on SrLaAlO$\text{}_{4}$ substrates. For each d the film sgrow with a variable strain, ranging from a large compressive strain in the thinnest films to a negligible or tensile strain in thick films. Our results indicate that the tensile strain is not caused by the off-stoichiometric layer at the substrate-film interface. Instead, it may be caused by the extreme oxygen deficiency in some of the films.
Źródło:: Acta Physica Polonica A; 2007, 111, 1; 185-188
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 4.

Tytuł:: Superconductivity Study of GaN Highly Doped by Transition Metals
Autorzy:: Gosk, J.
Boćkowski, M.
Tokarczyk, M.
Kowalski, G.
Twardowski, A.
Powiązania:: https://bibliotekanauki.pl/articles/1399142.pdf
Data publikacji:: 2013-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 74.25.Ha
74.70.-b
74.25.Dw
75.50.-y
61.72.Dd
81.10.Dn
Opis:: GaN:Cr and GaN:Fe single crystals as well as GaN:Mn micropowders highly doped by transition metals were grown to investigate low temperature superconductivity. Magnetic measurements revealed type I superconductivity with $T_{C} ≈ 6 K$ and $H_{C} ≈ 600 Oe$, identical for all compounds and also identical to that observed before in GaP:Cr and GaAs:Cr. The presence of amorphous inclusions of gallium may explain existing superconductivity as a result of a phase transition leading to β-Ga during cooling down of the sample. Since the observed parameters are close to those characteristic for superconducting Ga(II) this possibility could not be ruled out.
Źródło:: Acta Physica Polonica A; 2013, 124, 5; 877-880
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 5.

Tytuł:: Observation of Superconductivity in Highly Cr-Doped GaP Single Crystals
Autorzy:: Gosk, J. B.
Strzelecka, G.
Kowalski, G.
Hruban, A.
Kamińska, M.
Twardowski, A.
Gronkowski, J.
Powiązania:: https://bibliotekanauki.pl/articles/2046913.pdf
Data publikacji:: 2006-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 74.10.+v
75.50.Pp
61.72.Vv
61.72.Dd
81.10.Dn
Opis:: Studying bulk GaP, highly doped with Cr, and searching for possible ferromagnetic semiconductor in view of spintronic applications, we found superconducting behavior of this material unexpectedly. Magnetization techniques and X-ray diffraction were applied to study these crystals. Magnetization revealed superconducting features up to about 6 K and X-ray studies showed that superconductivity might be related to small size Cr precipitates.
Źródło:: Acta Physica Polonica A; 2006, 110, 2; 189-193
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

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