Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "74.70.-b" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 28
Tytuł:
Chemical Potential as a Detector of Phase Transitions in Solids
Autorzy:
Matlak, M.
Gosławska, E.
Grabiec, B.
Eid, Kh.
Powiązania:
https://bibliotekanauki.pl/articles/2012963.pdf
Data publikacji:
2000-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
75.30.Kz
75.40.Cx
Opis:
We show that the chemical potential exhibits small but distinct kinks at all critical temperatures as the evidence for phase transitions in the electronic system, structural phase transitions included. In the case of, at least, two kinds of interacting electrons average occupation numbers exhibit the same behavior.
Źródło:
Acta Physica Polonica A; 2000, 97, 3; 365-368
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Chemical Potential Evidence for Phase Transitions in Magnetic and Superconducting Compounds and Alloys
Autorzy:
Matlak, M.
Pietruszka, M.
Powiązania:
https://bibliotekanauki.pl/articles/2012914.pdf
Data publikacji:
2000-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
75.30.Kz
75.40.Cx
Opis:
We announce that all phase transitions (induced by temperature or concentration) including structural ones and transitions between metastable or "exotic" states can be detected by the chemical potential critical behaviour, as well as, from the average occupation numbers of the electronic system (critical electron redistribution).
Źródło:
Acta Physica Polonica A; 2000, 97, 1; 253-256
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of the Temperature Dependence of the Crystal Structure of $LiTi_2O_4$ and $LiV_2O_4$
Autorzy:
Moshopoulou, E.
Powiązania:
https://bibliotekanauki.pl/articles/1813759.pdf
Data publikacji:
2008-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
61.05.fm
Opis:
The normal spinel oxide $LiTi_2O_4$ is an exotic superconductor with $T_c$=11.2 K, while the isostructural neighbouring $LiV_2O_4$ exhibits heavy-fermion behaviour. The origin of their physics and the role of the spinel structure on their properties are yet unsolved issues, owing mainly to the complexity of the structure, the presence of subtle disorder, and the sample dependence of the physical properties. Especially and perhaps more importantly, the enormous difference in their low-temperature properties remains an open question. This question has only been addressed theoretically but (mainly because of the above problems) there were no experimental studies that sought to understand the clearly distinct behaviour of the two systems. Here, we contribute to the understanding of such distinct low-temperature behaviour by comparing the temperature dependence of the very basic structural properties of the two systems. Upon cooling from room temperature, the lattice parameter a decreases gradually in about the same way for both systems. However, below 20 K, a clear decrease in a of $LiV_2O_4$ as a function of temperature contrasts strongly with the almost constant value of a of $LiTi_2O_4$ in the same temperature range. Therefore subtle but clearly different structural signatures are coupled with the very divergent physical properties of the two systems and suggest new directions to the theory.
Źródło:
Acta Physica Polonica A; 2008, 113, 1; 399-402
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effect of Majorana Fermions on Andreev Spectroscopy of Multiband Topological Superconductors
Autorzy:
Silva, A.
Araújo, M.
Sacramento, P.
Powiązania:
https://bibliotekanauki.pl/articles/1402577.pdf
Data publikacji:
2015-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.10.Fd
71.10.Pm
71.10.Li
73.20.-r
74.45.+c
74.20.Rp
74.70.-b
Opis:
We introduce a model for a multiband topological superconductor with two orbitals per lattice site, in two spatial dimensions. Concentrating on the Andreev reflection problem, the appropriate wave function matching conditions for an interface with a normal single-band metal were previously derived in the framework of a quantum waveguide theory. This theory retrieves the correct number of Majorana fermion states as predicted by the topological index. We obtain the differential conductance as a function of bias voltage, which displays the contribution of the Majorana fermions. Interface disorder is also considered. By varying band structure parameters, topological transitions can be induced, whereby the number of the Majorana modes varies. We calculate the effect of such transitions on the differential conductance.
Źródło:
Acta Physica Polonica A; 2015, 128, 2; 210-212
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electron-Molecular Vibration Coupling in TTF-Based Donors
Autorzy:
Pokhodnia, K. I.
Powiązania:
https://bibliotekanauki.pl/articles/1933373.pdf
Data publikacji:
1995-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
Opis:
BEDT-TTF, BMDT-TTF and BEDO-TTF are well known thio-TTF and oxo-TTF (in the former case) derivatives on the basis of which cation-radical salts with 2D type of conductivity can be produced. In this work the comparative analysis of electron-molecular vibration coupling constants (obtained by MNDO quantum-chemical method) that describe the interaction between totally symmetric A$\text{}_{g}$ modes and electron on HOMO level is performed.
Źródło:
Acta Physica Polonica A; 1995, 87, 4-5; 815-818
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electronic Properties of High-Temperature Superconductor DyBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7}$ from Critical Fields and Specific Heat Studies
Autorzy:
Kołodziejczyk, A.
Kozłowski, A.
Chmist, J.
Zalecki, R.
Ściężor, T.
Tarnawski, Z.
Woch, W. M.
Powiązania:
https://bibliotekanauki.pl/articles/1929388.pdf
Data publikacji:
1993-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
76.30.-v
Opis:
The lower and upper critical fields, as well as the specific heat were measured as a function of temperature for good quality DyBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7}$ high-temperature superconductor in the vicinity of superconducting transition temperature T$\text{}_{c}$ = 91.2 K. The number of superconducting and normal state electronic quantities were determined basing on the Ginzburg-Landau-Abrikosov-Gorkov theory. It is argued that on the basis of this BCS-like theory one can describe the superconducting properties and, in combination with some information on the electronic structure, also the magnetic properties of high-temperature superconductors.
Źródło:
Acta Physica Polonica A; 1993, 84, 1; 127-138
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fault Current Limitation by 2G HTS Superconducting Transformer - Experimental Investigation
Autorzy:
Wojtasiewicz, G.
Powiązania:
https://bibliotekanauki.pl/articles/1398591.pdf
Data publikacji:
2016-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.90.+n
84.70.+p
84.71.-b
85.25.-j
85.25.Am
85.25.Qc
Opis:
Transformers represent one of the oldest and most mature elements in a power transmission and distribution network. The new superconducting transformers are smaller and lighter than conventional ones and they have lower power losses, too. Also, the new 2G superconducting tapes with high resistivity in the normal state allow to build transformers with high short-circuit strength. The short-circuit current limiting feature of the superconducting transformer, which is the most important benefit of replacing conventional windings by superconducting ones, provides protection and significantly reduces the wear and tear of circuit breakers and other substation power equipment. This paper describes the design and experimental investigations results of a model of a 1-phase, 8.8 kVA superconducting transformer with windings made of 2G HTS tape. A special regard is given to the ability of the device's superconducting winding to limit the short-circuit current, in particular its equivalent resistance in normal state at a temperature of 77 K (i.e. resistance of the resistive layers of the HTS tape just after transition to the non-superconducting state).
Źródło:
Acta Physica Polonica A; 2016, 130, 2; 516-520
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
First Principles Calculation of ε-Phase of Solid Oxygen
Autorzy:
Kamaruddin, K.
Abedin, A.
Zabidi, N.
Yahya, M.
Taib, M.
Rosli, A.
Powiązania:
https://bibliotekanauki.pl/articles/1398703.pdf
Data publikacji:
2016-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.20.Pq
74.70.-b
31.15.E-
75.50.Xx
Opis:
The electronic structures of ε-phase of solid oxygen (O₂)₄ are studied within the framework of density-functional theory. The intriguing molecule has been known to have magnetic properties at room temperature by applying pressure. Nevertheless, until now there was no evidence of band structure studied in the antiferromagnetic behaviour of (O₂)₄. We report a comparison study for spin and non-spin polarization orbital which suggests that this ferromagnetic configuration of (O₂)₄ could not be seen experimentally, and antiferromagnetic configuration of (O₂)₄ was seen at higher pressure of about 10 GPa. The antiferromagnetic state transforms into the superconducting state as the sample temperature decreases. The results can serve as a useful approximation in studying general features of the electronic structure. The (O₂)₄ clusters are reported in the Raman study, having significant absorption at 1516 cm¯¹ below infrared region.
Źródło:
Acta Physica Polonica A; 2016, 129, 4; 468-471
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Formation of Superconducting Regions of MgB_2 by Implantation of Boron Ions into Magnesium Substrate
Autorzy:
Trybuła, Z.
Kempiński, W.
Andrzejewski, B.
Piekara-Sady, L.
Kaszyński, J.
Piekoszewski, J.
Werner, Z.
Richter, E.
Prokert, F.
Stanisławski, J.
Barlak, M.
Powiązania:
https://bibliotekanauki.pl/articles/2043433.pdf
Data publikacji:
2005-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.78.-w
Opis:
The results of investigation of the MgB$\text{}_{2}$ inter-metallic compound with the use of boron ions implantation and plasma pulse treatment are presented. The samples were characterized by: four-probe electric conductivity measurements, magnetically modulated microwave absorption, and magnetic measurements. For hydrogen and argon pulsed plasma treatment the samples with T$\text{}_{c}$ ranging from 10 K to 32 K were obtained. The superconducting phase does not form a continuous layer since the resistivity does not fall down to zero. Apparently, separate islands of superconducting phase are connected through metallic Mg paths. All samples are still below the percolation threshold.
Źródło:
Acta Physica Polonica A; 2005, 108, 1; 165-170
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ion Implantation and Transient Melting: A New Approach to Formation of Superconducting MgB$\text{}_{2}$ Phases
Autorzy:
Piekoszewski, J.
Kempiński, W.
Stankowski, J.
Prokert, F.
Richter, E.
Stanisławski, J.
Werner, Z.
Szymczyk, W.
Powiązania:
https://bibliotekanauki.pl/articles/2041609.pdf
Data publikacji:
2004-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.78.-w
Opis:
An attempt to synthesize superconducting MgB$\text{}_{2}$ inter-metallic compound from the liquid state is presented. The process consists of two steps. In the first one, boron ions are implanted into a magnesium substrate. In the second one, the near-surface region of such system is melted by short, intense hydrogen plasma pulses without necessity of annealing in Mg vapor. A magnetically modulated microwave absorption method was used to detect superconducting regions in the obtained MgB$\text{}_{2}$ layer. Percolation between nano-regions (islands) of MgB$\text{}_{2}$ has not been observed. However, a superconducting state of the insulated islands has been experimentally proven with transition temperatures T$\text{}_{C}$ as high as 31 K.
Źródło:
Acta Physica Polonica A; 2004, 106, 6; 861-868
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of Milled and Thermal Relaxed YBa$\text{}_{2}$ (Cu$\text{}_{1-x}$Fe$\text{}_{x}$)$\text{}_{3}$O$\text{}_{y}$
Autorzy:
Timko, M.
Kováč, J.
Sargánková, I.
Zentková, M.
Mihalik, M.
Maťaš, S.
Čiasnohová, A.
Powiązania:
https://bibliotekanauki.pl/articles/1955517.pdf
Data publikacji:
1997-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.90.+n
74.10.+v
74.70.-b
Opis:
The influence of the mechanical milling and subsequent thermal relaxation on magnetic and superconducting behaviour of YBa$\text{}_{2}$(Cu$\text{}_{1-x}$Fe $\text{}_{x}$)$\text{}_{3}$O$\text{}_{y}$ system has been studied. Two methods of heat treatment were used: Set I - slow cooling from 980°C in flowing O$\text{}_{2}$ and Set II - reducing at 770°C in flowing Ar$\text{}_{2}$ followed by reoxidation in flowing O$\text{}_{2}$ below 400°C. The transition to superconductivity, diamagnetic response, critical current density and the effective magnetic moment in the normal state have been estimated. Our measurements indicate that the reducing atmosphere preparation is less detrimental on superconducting properties. The results are discussed in terms of occupancy Cu sites by Fe and redistribution of oxygen atoms.
Źródło:
Acta Physica Polonica A; 1997, 91, 2; 355-358
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microwave Absorption Study on (Bi,Pb)-Sr-Ca-Cu-O Granular Superconductors
Autorzy:
Jurga, W.
Piekara-Sady, L.
Gazda, M.
Powiązania:
https://bibliotekanauki.pl/articles/1812335.pdf
Data publikacji:
2008-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.72.-h
74.45.+c
Opis:
(Bi,Pb)-Sr-Ca-Cu-O is considered as a system of 2201, 2212 and 2223 superconductors embedded in the insulating matrix. The size of the grains depends on the time of recrystallization. These types of ceramics exhibit a two-step transition to superconducting state. Because electrical properties depend among other on the Josephson coupling between grains, the magnetically modulated microwave absorption study was undertaken. Magnetically modulated microwave absorption signal was observed to arise just as temperature had been lowered below T₁. The shape of this signal was studied to recognize the second temperature T₂. Some strong oscillations appear on magnetically modulated microwave absorption at lower temperatures, which might be related to local percolation breakdown in superconducting network.
Źródło:
Acta Physica Polonica A; 2008, 114, 1; 253-256
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Negative Magnetisation and Absence of Superconductivity in RFe$\text{}_{4}$Al$\text{}_{8}$ (R=Lu, Yb) Compounds
Autorzy:
Andrzejewski, B.
Kowalczyk, A.
Toliński, T.
Powiązania:
https://bibliotekanauki.pl/articles/2046747.pdf
Data publikacji:
2006-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.Dd
75.50.-y
75.50.Ee
51.60.+a
74.70.-b
Opis:
We report researches for superconductivity and the effect of negative magnetisation in the RFe$\text{}_{4}$Al$\text{}_{8}$ (R = Lu, Yb) compounds by means of magnetic measurements and microwave absorption. Contrary to the earlier reports we do not confirm the existence of any traces of superconductivity in these compounds. Instead of the superconductivity and the Meissner effect, the YbFe$\text{}_{4}$Al$\text{}_{8}$ compound exhibits the effect of negative magnetisation, whereas the LuFe$\text{}_{4}$Al$\text{}_{8}$ compound shows an exact antiferromagnetic behaviour.
Źródło:
Acta Physica Polonica A; 2006, 109, 4-5; 561-564
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the Surfacegrived State of Cleaved YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ Single Crystals
Autorzy:
Harm, S.
Mante, G.
Manzke, R.
Fink, J.
Skibowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1920917.pdf
Data publikacji:
1992-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
79.60.-i
Opis:
Angle-resolved photoemission experiments on the cleaved surface of YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ single crystals revealed an intrinsic surface-derived electronic state around the X and Y point of the Brillouin zone with 0.92 eV binding energy. A surface electronic structure different to the bulk can be of basic importance for the surface superconductivity of this high-T$\text{}_{c}$ cuprate. Here we briefly review recent experimental results and present new hydrogen adsorption experiments, demonstrating the surface character of the 0.92 eV state.
Źródło:
Acta Physica Polonica A; 1992, 82, 2; 349-354
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Phase Diagram and Activation Energy for Vortex Pinning in Nb/(Co,Pd) Superconductor-Ferromagnet Bilayer
Autorzy:
Syryanyy, Y.
Aleszkiewicz, M.
Cieplak, Marta
Zhu, L.
Chien, C.
Powiązania:
https://bibliotekanauki.pl/articles/1374109.pdf
Data publikacji:
2014-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.F-
74.25.N-
74.25.Wx
74.62.-c
74.70.-b
74.78.-w
74.78.Fk
75.70.Kw
75.70.-i
Opis:
Using the magnetoresistance measurements we study the phase transition line and the activation energy for vortex pinning in superconductor/ferromagnet bilayer, built of a ferromagnetic Co/Pd multilayer with perpendicular magnetic anisotropy, and a niobium film, with insulating layer in-between to eliminate proximity effect. The domain width is reversibly pre-defined using the angle-dependent demagnetization. We find that the enhancement of the activation energy for vortex pinning by magnetic domains is rather modest, by a factor of about 2.1. We attribute this to large domain width, and large dispersion of the domain width in this bilayer.
Źródło:
Acta Physica Polonica A; 2014, 126, 4a; A-123-A-126
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 28

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies