Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
Polish version English version Language
enabled [disable] Abstract
Number of results

Results found: 22

Number of results on page
first rewind previous Page / 2 next fast forward last

Search results

Search:
in the keywords:  72.15.-v
help Sort By:

help Limit search:
first rewind previous Page / 2 next fast forward last
1
Content available remote

Magnetoresistance of the CeCo_{1-x}Fe_xGe₃ Alloys

100%
Skokowski P., Synoradzki K., Toliński T.
Acta Physica Polonica A
|
2017
|
vol. 131
|
issue 4
1000-1002
EN
A transition from CeCoGe₃ to the CeFeGe₃ compound, i.e. the CeCo_{1-x}Fe_xGe₃ series has been studied by magnetoresistance measurements. Previously, it was reported that at the concentration x ≈ 0.6 the system is in the vicinity of the quantum critical point. In the present research we have performed the isothermal magnetoresistivity investigations (down to 2K) on polycrystalline samples with x = 0.3, 0.4, and 0.6 to gain further insight into the possible existence of quantum critical point in the CeCo_{1-x}Fe_xGe₃ series. Additionally, electrical resistivity as a function of temperature has been measured and analyzed showing features of non-Fermi liquid behavior at low temperatures.
2
Content available remote

Analysis of the Nanocrystalline Phase Formation Process in Amorphous Fe-X-Si-B Alloys

63%
Stokłosa Z., Kwapuliński P., Rasek J., Ilczuk J., Lelątko J.
Acta Physica Polonica A
|
1996
|
vol. 89
|
issue 3
437-442
EN
The process of nanocrystalline phase formation, affecting magnetic properties, in amorphous Fe_{78}Si_{8}B_{14}, Fe_{76}Al_{2}Si_{8}B_{14}, Fe_{76}Cr_{2}Si_{8}B_{14} and Fe_{76}Mo_{2}Si_{8}B_{14} alloys has been studied in the paper. Investigations have been carried out using the electrical resistivity method, magnetic methods, transmission electron microscopy and X-ray diffraction. A nanocrystalline phase in the amorphous matrix has been obtained by isochronous or isothermal vacuum annealing. Phase composition of samples has been determined directly after manufacturing and after crystallization annealing on the basis of X-ray diffraction and electron diffraction. Transmission electron microscopy was used to determine phase morphology, dimensions of formed nanocrystalline phase and transition phase. Alloying elements have been found to affect changes of magnetic properties in amorphous and nanocrystalline states. For Fe_{76}Mo_{2}Si_{8}B_{14} alloys a significant increase in crystallization temperature, making difficult nanocrystalline phase growth and increase in thermal stability of magnetic permeability have been observed.
3
Publication available in full text mode
Content available

Magnetic and Transport Properties of R_3Cu_3Sb_4 Compounds (R = La, Ce, Pr, Nd, and Sm)

51%
Skolozdra R., Baran M., Horyn A., Szewczyk A., Gorelenko Y., Szymczak H., Szymczak R.
Acta Physica Polonica A
|
2002
|
vol. 102
|
issue 3
429-435
EN
Magnetic susceptibility, electrical resistivity, and thermopower of the series of the R_3Cu_3Sb_4 compounds (R=La-Sm) were measured over the temperature ranges 1.9-300 K (susceptibility and resistivity) and 80-370 K (thermopower). Below 25 K, resistivity of these compounds grows exponentially with decreasing temperature. For some compounds, R = Ce, Sm, a maximum on temperature dependence of resistivity is observed. Ce_3Cu_3Sb_4 compound undergoes a magnetic transition at 12 K.
4
Content available remote

Characterization of New U-Ni-X₂ Splats and Study of their Physical Properties

51%
Molčanová Z., Mihalik M., Mihalik M., Reiffers M., Džubinská A., Huráková M., Kavečanský V., Paukov M., Havela L.
Acta Physica Polonica A
|
2017
|
vol. 131
|
issue 4
994-996
EN
We explored the crystal structure, magnetic, and transport properties of UNiX₂ (X = Ge, Si) materials, which were prepared by a conventional metallurgical technique and by rapid solidification - splat cooling. The UNiSi₂ splat is mostly single phase, containing only small traces of a minority phase. Magnetic and electrical properties of the splat resemble properties of samples, which were prepared by conventional methods, exhibiting a ferromagnetic transition at about 91 K and similar temperature dependence of resistivity. The coercive field of μ₀H_c=4.25 T is much enhanced due to the magnetic anisotropy introduced by the sample preparation technique. The Barkhausen jumps were observed on the hysteresis loop. Magnetization of the sample does not saturate in fields up to μ₀H=9 T. The phase structure of UNiGe₂ splat is not completely solved and will be subject of our study in future. Our preliminary results indicate the presence of completely new phase with tetragonal crystal structure and antiferromagnetic ordering below 54 K.
5
Content available remote

Some Electronic Properties of Sr_{1-x}A_{x}CuO_{2+δ} where A=La, K, and Ca

51%
Onyszkiewicz I., Czarnecki P., Poltoracky Y., Zimpel M.
Acta Physica Polonica A
|
1994
|
vol. 85
|
issue 2
303-306
EN
The electronic properties of Sr_{1-x}A_{x}CuO_{2+δ} (A = La, K, Ca) were examined. The crystal structure of the synthesized compounds was identified as orthorhombic with some admixture of tetragonal phase. For Sr_{1-x}La_{x}CuO_{2+δ} the insulator-metal like transition was observed with increasing La content. The d_{x²-y²} ground state of Cu ions was deduced from electron spin resonance measurements. The electronic state of Cu ions and their surrounding local symmetry was also found to be La and oxygen content dependent.
6
Content available remote

Band Structure and Magnetic Properties of DO_{3}-Type Fe_{3-x}V_{x}Al Alloys. Super-Cell Approach

51%
Deniszczyk J., Borgieł W.
Acta Physica Polonica A
|
2000
|
vol. 98
|
issue 5
551-554
EN
The electronic structure of Fe_{3-x}V_{x}Al alloys was calculated using the super-cell methodology of alloy modeling. The concentration range of x=0.0÷1.0 was investigated. For a concentration of x=0.0625 the energy based analysis reveals that vanadium prefers to replace the Fe atom at sites with the octahedral coordination. It was found that the iron atoms coordinated by the eight nearest-neighbor Fe atoms preserve their high magnetic moment up to a concentration of x=0.9375 even though the average total magnetic moment goes to zero. The relatively high (≃ -1.0μB) negative magnetic moment of V remains constant up to x≃ 0.5. In the concentration range of x=0.75÷0.9375 the gap at ε_{F} of the minority density of states is observed while the majority density of states displays a sharp peak structure at the Fermi energy. This feature suggests the heavy-fermion behavior of the Fe_{2}VAl compound.
7
Content available remote

Resistivity of (Gd_{1-x}Y_{x})_{2}In Alloys at High Temperatures - Two-Band Model Approach

51%
Borgieł W., Deniszczyk J., Lipowczan M., Braun J.
Acta Physica Polonica A
|
2000
|
vol. 98
|
issue 5
547-550
EN
Two-band model for the substitutionary binary alloy of different rare earth metals with relatively simple 4f multiplet structure placed within the transition metal host matrix was proposed and applied to (Gd_{1-x}Y_{x})_{2}In. The main interaction which causes the magnetic part of the resistivity was assumed in a form of stochastically distributed in space s-f interaction. The calculated high temperature spin disorder resistivity of (Gd_{1-x}Y_{x})_{2}In alloys reproduces well the experimental alloys data.
8
Content available remote

Quantum Interference in Disordered Ferromagnet U₂NiSi₃

51%
Gnida D., Szlawska M., Wiśniewski P., Kaczorowski D.
Acta Physica Polonica A
|
2015
|
vol. 127
|
issue 2
451-453
EN
A single-crystalline sample of disordered ferromagnetic U₂NiSi₃ was investigated by means of electrical resistivity measurements under ambient and high hydrostatic pressure. Temperature dependences of the electrical resistivity clearly reveal interplay of the ferromagnetic ordering and quantum interference effects resulting from crystallographic disorder. Electron-electron interaction manifests itself as a T^{0.5} increase in the in-plane and out-of-plane electrical resistivity below 5 K. Weak localization is observed solely in the ab-plane as a linear-in-T contribution to resistivity, which suggests that internal magnetic field does not break the interference of scattered electron waves in ab-plane. Applied hydrostatic pressure does not affect the T^{0.5} electron-electron interaction contribution, however it diminishes the impact of weak localization on the ab-plane resistivity.
9
Content available remote

Low-Temperature Physical Properties of Single-Crystalline EuCoGe₃ and EuRhGe₃

51%
Bednarchuk O., Kaczorowski D.
Acta Physica Polonica A
|
2015
|
vol. 127
|
issue 2
418-420
EN
Since a few years europium-based intermetallics have been attracting more and more attention due to their intriguing physical properties with anomalous behaviours in magnetically ordered states. Here, we report on the formation and the bulk physical properties of two tetragonal compounds EuCoGe₃ and EuRhGe₃, studied on high-quality single-crystalline specimens. In both materials, the Eu ions are in their divalent state, which gives rise to an antiferromagnetic ordering below T_{N} = 15.4 K and T_{N} = 11.3 K, respectively. In addition, EuCoGe₃ exhibits a successive antiferromagnetic phase transition at T₂ = 13.4 K. Based on some characteristic features in the temperature variations of the magnetic susceptibility, specific heat and electrical resistivity, we suggest that in both germanides an amplitude modulated magnetic structure develops below the respective T_{N}, with the Eu magnetic moments directed along the crystallographic [001] axis in EuCoGe₃ and perpendicular to this direction in EuRhGe₃.
10
Content available remote

Electron Transport Properties of UAsSe

51%
Henkie Z., Fabrowski R., Wojakowski A.
Acta Physica Polonica A
|
1994
|
vol. 85
|
issue 2
249-252
EN
Anisotropy of resistivity (2-450 K), in-plane thermoelectric power (4-300 K) and Hall's constants (200-450 K) for UAsSe were determined. It is highly anisotropic, uniaxial ferromagnet below T_{C} = 113 K. The compound is classified as Kondo lattice system becoming noncoherent below ≈ 0.5T_{C}.
11
Content available remote

Magnetic and Electronic Properties in Series of GdT_{x}Ga_{4-x} Solid Solutions (T = Ni or Cu)

51%
Wiśniewski P., Gorzelniak R., Kaczorowski D.
Acta Physica Polonica A
|
2015
|
vol. 127
|
issue 2
382-384
EN
We present results of extensive measurements of magnetic susceptibility, electrical resistance, specific heat and thermoelectric power of two series of solid solutions GdNi_{x}Ga_{4-x} and GdCu_{x}Ga_{4-x}, for ranges of doping x from 0.6 to 1 and from 1 to 1.5, respectively. All studied phases display the Curie-Weiss behaviour of magnetic susceptibility and antiferromagnetic ordering at temperatures below 23 K. Substitution of gallium with transition metal atoms has strong influence on Néel temperatures of all studied phases, shifting them by few K, depending on x. Metamagnetic-like anomalies are observed for some compositions. Behaviour of the electrical resistivity reveals metallic nature of all samples. Their magnetic ordering is reflected in low-temperature anomalies of the resistivity and the heat capacity.
12
Content available remote

Residual Resistivity Due to Vacancies in Alkali Metals

51%
Gajjar P. N., Thakore B. Y., Luhar J. S., Jani A. R.
Acta Physica Polonica A
|
1994
|
vol. 86
|
issue 3
369-374
EN
We have used a pseudopotential technique to examine the contribution of monovacancy, which is one of the point defects, to the resistivity of alkali metals. Two different forms of the bare-ion local pseudopotential, to describe the electron-ion interaction in metals, have been employed in the present work. Various forms of the dielectric function lave been used to incorporate the exchange and correlation effects among the conduction electrons. Varying effect of dielectric functions on the computed results is concluded while comparing our findings with other theoretical data.
13
Content available remote

Electronic Structure and Electron-Transport Properties of (Gd_{1-x}Y_{x})_{2}In Compounds

51%
Borgieł W., Deniszczyk J.
Acta Physica Polonica A
|
2000
|
vol. 97
|
issue 5
783-786
EN
Based on the electronic structure of the ferromagnetic Gd_{2}In and (Gd_{0.5} Y_{0.5})_{2}In compounds the high-temperature magnetic part of the electrical resistivity of (Gd_{1-x}Y_{x})_{2}In as a function of Y concentration was calculated and analyzed. The main interaction which causes the finite magnetic part of the conductivity was assumed in a form of stochastically distributed in space s-f interaction. The calculated resistivity of (Gd_{1-x}Y_{x})_{2}In alloys qualitatively reproduces the experimental data.
14
Content available remote

Electrical Conductivity for the Strongly Correlated and Hybridized Hubbard Band

51%
Kosimow R., Borgieł W., Deniszczyk J.
Acta Physica Polonica A
|
2000
|
vol. 97
|
issue 5
799-802
EN
The magnetic and electrical transport properties of strongly correlated Hubbard band (f-band) hybridizing with the non-correlated conduction band (c-band) was studied. The many-body model Hamiltonian was treated within the modified alloy analogy scheme and the resulting one-body problem was solved with the use of coherent potential approximation. Within the Kubo-Greenwood formalism the dc electrical conductivity for bcc magnetic system was calculated and its variation with temperature and number of electrons was examined for different values of the Coulomb and hybridization (V) coupling constants. We found that the effect of strong correlations and hybridization on the conductivity is similar to that produced by the scattering due to the s-f interaction (spin disorder resistivity).
15
Content available remote

Ab Initio Studies on Structural, Elastic, Thermodynamic and Electronic Properties of FeCrAs under Pressures

51%
He D.-C., Peng Y., He Y.-W.
Acta Physica Polonica A
|
2015
|
vol. 127
|
issue 6
1637-1644
EN
The structural, elastic, thermodynamic and electronic properties of nonmetallic metal FeCrAs are studied within density function perturbation theory. The thermodynamic properties of FeCrAs were deduced based on phonon frequencies within the framework of the quasiharmonic approximation. The calculated elastic modulus under various pressures indicates that FeCrAs is mechanically stable under pressure. The pressure-dependence of bulk and shear modulus, transverse and longitudinal sound velocities V (i.e. V_{S} and V_{L}), elastic Debye temperature Θ_{E} of FeCrAs have also been investigated. The calculated values of B/G indicate that FeCrAs presents high ductility under pressure. However, it is interesting that the value of B/G reaches a maximum under 40 GPa and almost remains unchanged when the pressure is above 70 GPa. The calculations show that the heat capacity C_{V} of this material is close to the Dulong-Petit limit 3R (about 224.61 J mol^{-1} K^{-1}) at high temperature regime. The analysis of electronic properties find that as the pressure increases, the absolute value of charge for As and Fe atom increases while Cr remains nearly a constant, indicating that the mechanic properties of FeCrAs under pressure should be mostly attributed to the interaction between Fe and As atoms.
16
Content available remote

Metal-Dielectric Transition in Hydrogen

51%
Shvets V., Vlasenko A.
Acta Physica Polonica A
|
2008
|
vol. 114
|
issue 4
851-858
EN
The electrical resistivity of liquid metallic hydrogen at a temperature of 3000 K and a density of 0.35 mol/cm^3 is calculated. Hydrogen is considered as a three-component system consisting of electrons, protons, and neutral hydrogen atoms. The second order of perturbation theory in electron-proton and electron-atom interactions is used to determine the inverse relaxation time for electric conductivity. The Coulomb electron-electron interaction is taken into account in the random phase approximation and the exchange interaction and correlation of conductivity electrons are included in the local-field approximation. The model of hard spheres is used for the proton and atomic subsystems. The concentration of the electrically neutral atomic component proved to be significantly lower than the value assumed by the discoverers of metallic hydrogen.
17
Content available remote

Anisotropy of Susceptibility and Optical investigation of the Antiferromagnetic phase Transition in U_{1-x}Ce_{x}Ru_{2}Si_{2}

51%
Mihalik M., Maťaš S., Macko D., Timko M., Menovsky A. A.
Acta Physica Polonica A
|
1997
|
vol. 91
|
issue 2
351-354
EN
Temperature dependence of magnetic susceptibility of U_{1-x}Ce_{x}Ru _{2}Si_{2} single crystals (x=0, 0.025, 0.05, 0.075) has been studied at temperatures from 4.2 K up to room temperature and in magnetic fields applied along and perpendicular to the c-axis. The attention was paid to anomalies connected with the antiferromagnetic phase transition, which are present in crystals with x≤0.05. Far-infrared measurements of U_{0.99}Ce_{0.01} Ru_{2}Si_{2} single crystal have been studied for the first time. The measurements support the assumption that the origin of magnetic ordering in U_{0.99}Ce_{0.01}Ru_{2}Si_{2} is the same as in heavy-fermion superconductor URu_{2}Si_{2} and can be interpreted as being due to a spin-density-wave gap.
18
Content available remote

Electronic Transport Properties and Growth Mechanisms of Ni-Fe/Au/Co/Au Multilayers from In Situ Conduction Measurements

51%
Błaszyk M., Kempiński M., Buchta K., Chomiuk P., Luciński T.
|
|
issue 5
861-863
EN
In the following we present the role of surface scattering at Au/Co and Au/Ni-Fe interfaces in Ni-Fe/Au/Co/Au multilayers deposited in different temperatures. Specularity parameter, which describes the electron scattering, is calculated from fitting in situ collected conductance data with the Fuchs-Namba-Tesanovic model. Application of the parallel resistors model enabled to depict changes between Au/Co and Au/Ni-Fe interfaces within multilayers for each repetition. The correlation between enhanced grain boundary scattering for higher deposition temperatures and surface roughness of Ni-Fe/Au/Co/Au multilayers is found.
19
Content available remote

Electrical Resistivity and Electronic Structure of the Tb_{x}Gd_{1-x}Ni_3 System

45%
Chełkowska G., Bajorek A., Chrobak A., Kwiecień-Grudziecka M.
Acta Physica Polonica A
|
2012
|
vol. 121
|
issue 5-6
1139-1141
EN
In the paper the electric properties and electronic structure of the intermetallic Tb_{x}Gd_{1-x}Ni_3 compounds are presented. The partial replacement of Gd by Tb atoms causes the decrease of the Curie temperature (T_{C}) and the increase of the residual resistivity. According to the Matthiessen rule the scattering mechanisms in ρ(T) have been analyzed. Moreover, the reduced form of the electrical resistivity ρ_{Z} (T - T_{0}) indicates a deviation from the linearity for x > 0.2. This kind of behaviour can be attributed to density of d states near by the Fermi level (E_{F}) which are dominated by Ni 3d states. The valence band spectra as well as the core level lines have been analyzed as the influence of Tb/Gd substitution on the electronic structure.
20
Content available remote

Influence of Chemical Composition of Liquid Phase and Growth Process on Physical Properties of Bi_2Se_3, Bi_2Te_3 and Bi_2Te_2Se Compounds

45%
Hruban A., Materna A., Dalecki W., Strzelecka G., Piersa M., Jurkiewicz-Wegner E., Diduszko R., Romaniec M., Orłowski W.
Acta Physica Polonica A
|
2011
|
vol. 120
|
issue 5
950-953
EN
We studied synthesis and crystal growth of Bi_2Te_3, Bi_2Se_3 and Bi_2Te_2Se compounds by means of vertical Bridgman method. Crystals were grown from stoichiometric melts and under different molar ratio of Bi:Te, Bi:Se or Bi:Te:Se. The obtained crystals were characterized by X-ray diffraction analysis, energy dispersive X-ray spectroscopy, scanning electron microscopy, atomic force microscopy, and the Hall effect measurements. Some of the samples demonstrated insulating bulk behavior, by means of resistivity versus temperature measurements.
first rewind previous Page / 2 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.