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: 27

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

Search results

help Sort By:

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

Magnetic Anisotropy of Fe Films in MgO/Cu(t_{Cu})/Fe/Cu Systems

100%
Baszyński J., Toliński T.
Acta Physica Polonica A
|
1997
|
vol. 91
|
issue 2
245-248
EN
Ferromagnetic resonance was employed to study the magnetic anisotropy of the Fe thin film in the MgO/Cu(t_{Cu})/Fe/Cu system. The Fe film showed strong fourfold cubic anisotropy (H_{K_{1}} = 2K_{1}/M = 46.15 kA/m) for t_{Fe} = 23 nm and t_{Cu} = 0. The spread of the crystallographic axes Δβ = 0.5° was evaluated from the angular dependence of the resonance line width ΔH_{pp} (4.4 < ΔH_{pp} < 6.4 kA/m). Such a small mosaicity confirmed the epitaxial growth of the Fe film. The Cu buffer layer destroys this growth of the Fe film which showed only a weak anisotropy.
2
Content available remote

Magnetotunneling Experiments Using La_{0.7}Sr_{0.3}MnO_{3} Based Break Junctions

100%
Baszyński J., Toliński T.
Acta Physica Polonica A
|
2000
|
vol. 98
|
issue 5
567-570
EN
The La_{0.7}Sr_{0.3}MnO_{3} perovskite is a ferromagnetic half-metal with a strong spin polarization and high Curie temperature T_{C} (355K). We have shown that a combination of the break junction technique with the special properties of the La_{0.7}Sr_{0.3}MnO_{3} perovskite can lead to extremely high values of tunneling magnetoresistance ratio (> 10^{3}%) and high field sensitivity (30%/Oe). These results are obtained in magnetic fields below 1kOe and at room temperature.
3
Content available remote

Magnetic Properties of CeNi₄Mn_{y}Al_{1-y} Compounds

100%
Synoradzki K., Toliński T.
Acta Physica Polonica A
|
2015
|
vol. 127
|
issue 2
210-212
EN
The magnetic properties of the polycrystalline CeNi₄Mn_{y}Al_{1-y} compounds have been investigated combining AC susceptibility, field-cooled and zero-field-cooled DC magnetization and magnetic relaxation measurements. The X-ray diffraction measurements showed that the group CeNi₄Mn_{y}Al_{1-y} is isostructural and crystallizes in the CaCu₅-type structure (P6/mmm). For 0 < y < 1 irreversible magnetism, long-time magnetic relaxation effect and evident upshift of the AC susceptibility peak with increasing frequency are observed at low temperatures. The spin-glass-like behaviour originates from disorder due to the statistical occupation of the 3g site. Using our data we have constructed the tentative phase diagram.
4
Content available remote

Magnetic Properties of Ce(Cu_{x}Ni_{1-x})_{4}Mn Compounds

100%
Synoradzki K., Toliński T.
|
|
vol. 126
|
issue 1
300-301
EN
The Ce(Cu_{x}Ni_{1-x})_{4}Mn series of compounds has been studied for a wide range of the x values. The magnetic properties are determined from the temperature dependence of the dc and ac magnetization. A large irreversibility is observed between the zero-field cooled (ZFC) and field-cooled (FC) curves with a maximum in the ZFC one. The ac magnetic susceptibility also shows a peak, which shifts to higher temperatures with increasing frequencies, which is typically observed in spin-glass (SG) systems. The observation of the SG behaviour is further supported by a very slow decay of the isothermal remanent magnetization and by the typical shape of the magnetization curves. A range of x values showing the para-ferromagnetic-SG transitions has been found.
5
Content available remote

Grain-Size Effect on the Magnetocaloric Properties of the DyCo_{3}B_{2} Compound

100%
Toliński T., Synoradzki K.
|
|
vol. 126
|
issue 1
160-161
EN
The compound DyCo_{3}B_{2} has been recently found to show a significant magnetocaloric effect (MCE) at the ferromagnetic ordering temperature T_{C}=22 K. In the present study we verify the influence of the mechanical milling, i.e. the grains size effect on the characteristic parameters describing MCE. The grain size has been determined after each milling time by X-ray diffraction. MCE has been extracted from both the isothermal magnetization and the specific heat measurements. It is found that even a long milling does not spoil significantly the MCE parameters and only t_{m}>5 h reduces noticeably the value of the magnetic susceptibility, the isothermal magnetic entropy change and the relative cooling power.
6
Content available remote

Specific Heat of the Ce(Ni_{1 - x}Cu_{x})_4Mn Compounds

100%
Synoradzki K., Toliński T.
Acta Physica Polonica A
|
2012
|
vol. 121
|
issue 5-6
1079-1081
EN
Specific heat of the Ce(Ni_{1 - x}Cu_{x})_4Mn compounds has been studied. The samples are prepared by induction melting and it is found, based on the X-ray diffraction, that all the compounds keep the CaCu_5-type structure. This series exhibits a transition between the ferromagnetically ordered CeNi_4Mn and the spin-glass CeCu_4Mn compounds, which is well visible in the measurements of the ac susceptibility peak as a function of the magnetic field frequency and in the magnetization relaxation. In the present research we explore the behavior of the specific heat for various x. The changes of the electronic specific heat coefficient γ are determined by analysis of the low temperature part of the C_{p}/T(T^2) dependence. We also observe that the magnetic phase transition is only detectable in the specific heat signal after extraction of the magnetic contribution of the Mn atoms. This is carried out by subtraction of the specific heat of the reference sample.
7
Content available remote

Thermoelectric Properties of CeCu_4Ag Compound

81%
Kowalczyk A., Toliński T., Falkowski M., Timko M.
|
|
issue 5
936-937
EN
The magnetic and electronic properties including electrical resistivity, thermal conductivity and thermopower are discussed for the heavy fermion CeCu_4Ag compound. The electrical resistivity shows a Kondo-like logarithmic increase up to a maximum at T = 75 K. Thermopower is positive over the whole temperature range and below T_max = 25 K falls rapidly. The measured thermal conductivity of the CeCu_4Ag compound increases with increasing temperature.
8
Content available remote

Magnetoresistance of the CeCo_{1-x}Fe_xGe₃ Alloys

81%
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.
9
Publication available in full text mode
Content available

Negative Magnetisation and Absence of Superconductivity in RFe_4Al_8 (R=Lu, Yb) Compounds

81%
Andrzejewski B., Kowalczyk A., Toliński T.
Acta Physica Polonica A
|
2006
|
vol. 109
|
issue 4-5
561-564
EN
We report researches for superconductivity and the effect of negative magnetisation in the RFe_4Al_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_4Al_8 compound exhibits the effect of negative magnetisation, whereas the LuFe_4Al_8 compound shows an exact antiferromagnetic behaviour.
10
Content available remote

Correlation between Magnetic Phases and Insulator-Metal Transition in La_{1/3}Nd_{1/3}Ca_{1/3}MnO_{3} Perovskite

81%
Baszyński J., Idzikowski B., Toliński T., Hoser A.
Acta Physica Polonica A
|
2000
|
vol. 97
|
issue 5
779-782
EN
The La_{1/3}Nd_{1/3}Ca_{1/3}MnO_{3} ceramic perovskites are investigated using the neutron diffraction technique and resistance measurements in the temperature range from 260 K down to 5 K. We have found that the integrated intensity of the antiferromagnetic peaks was growing with decreasing temperature and reached the maximum at a temperature about 20 K lower than that of the semiconductor-metal transition and did not vanish at 5 K. The semiconductor-metal transition is correlated with the temperature of the maximum of the lattice c-parameter and the percolation of ferromagnetic domains. Our results suggest that although the ferromagnetic long-range order is established through the semiconductor-metal transition induced percolation network, locally the antiferromagnetic correlation can remain.
11
Content available remote

Enhanced Thermoelectric Power Factors in the Ce(Ni_{1-x}Cu_{x})₂Si₂ and CeNi₂(Si_{1-y}Ge_{y})₂ Alloys

81%
Synoradzki K., Toliński T., Koterlyn M.
Acta Physica Polonica A
|
2018
|
vol. 133
|
issue 3
366-368
EN
In the presence of hybridization of the f states with the conduction electrons Ce-based compounds can show large peaks in the temperature dependence of the Seebeck coefficient, which makes them interesting materials for applications. The Seebeck coefficient and electrical resistivity of the bulk, arc-melted, single phase samples of Ce(Ni_{1-x}Cu_{x})₂Si₂ and CeNi₂(Si_{1-y}Ge_{y})₂ alloys were measured over the temperature range of 2 K to 300 K. All the samples exhibited a positive Seebeck coefficient, which reaches up to ım50μV/K at 150 K and it can be shifted up to 300 K by appropriate doping. The thermoelectric power factor, PF = S²/ρ, reached a maximum of 1.4×10¯³ Wm¯¹K¯² at 290 K and 1.1×10¯³ Wm¯¹K¯² at 110 K for x=0.25 and y=0.75, respectively. For selected representatives of the studied series thermoelectric properties have been measured up to 1000 K.
12
Content available remote

Magnetocaloric Effect in NdNi_4Si Compound

81%
Falkowski M., Toliński T., Kowalczyk A.
Acta Physica Polonica A
|
2012
|
vol. 121
|
issue 5-6
1290-1292
EN
On the basis of the thermodynamic approach, we report the magnetocaloric properties of the ternary ferromagnetic NdNi_4Si compound with magnetic phase transition temperature T_{C} at 8 K. The saturated magnetic moment in H = 9 T is equal to 1.5 μ_{B}/f.u. at 4.2 K and the compound crystallizes in the hexagonal CaCu_5-type structure (space group P6/mmm). The magnetocaloric effect was calculated in terms of the isothermal magnetic entropy change Δ S_{M} as well as the adiabatic temperature change Δ T_{ad} using the specific heat data and magnetization measurements. Within the second order phase transition significant values of these parameters have been observed.
13
Content available remote

Neutron Diffraction Study of Ferromagnetic Ordering in La_{1/3}Nd_{1/3}Ca_{1/3}MnO_{3} Induced by Electric Field

81%
Baszyński J., Idzikowski B., Toliński T., Hoser A.
Acta Physica Polonica A
|
2000
|
vol. 97
|
issue 5
831-834
EN
We used the neutron diffraction technique to study the ferromagnetic ordering process in La_{1/3}Nd_{1/3}Ca_{1/3}MnO_{3} induced by the short impulse of the external electric field E=4 V/cm at a magnetic field H=1.5 T. Our sample was prepared by the standard solid-state reaction. The diffraction measurements at 4 K, carried out for the neutron wavelength λ=0.2442 nm, have revealed the orthorhombic perovskite structure with the unit-cell parameters: a=0.5480 nm, b=0.5550 nm and c=0.7737 nm. We observed that a short impulse of the electric field develops the ferromagnetic ordering in a similar way as the magnetic field up to 4 T. We assume that the increased ferromagnetic ordering induced by the external electric field at a given magnetic field has the same physical origin as in the case of the Zener double exchange. The effect is confirmed by magnetic moment measurements using vibrating sample magnetometer.
14
Content available remote

Thermoelectric Power of the URu_{1-x}Pd_{x}Ge System

81%
Gralak D., Toliński T., Tran V.
Acta Physica Polonica A
|
2015
|
vol. 127
|
issue 2
287-289
EN
We report the measurements of thermoelectric power, S(T), of the URu_{1-x}Pd_{x}Ge solid solutions in the temperature range 1.9-300 K. It is found that S(T) of URuGe is consistent with the behaviour of Kondo lattice, characterized by a low-temperature negative minimum and a high-temperature positive maximum. On the contrary, S(T) of the compositions 0.1 ≤ x ≤ 0.7 is negative over the whole temperature range measured and shows only one negative minimum around 200 K. The compositions x = 0.9 and 1, in addition to a high-temperature negative minimum, exhibit anomalies at low temperatures, presumably associated with the magnon drag. We interpret the experimental data assuming the presence of the Kondo and crystal-electric field effects.
15
Content available remote

Specific Heat of YbNi_4Si Compound

81%
Falkowski M., Kowalczyk A., Toliński T.
Acta Physica Polonica A
|
2008
|
vol. 113
|
issue 2
641-644
EN
The specific heat of YbNi_4Si has been analyzed considering the electronic contribution and the lattice contributions in frames of the Debye model. Based on the specific heat measurements, the electronic specific heat coefficient γ = 25 mJ mol^{-1} K^{-2} and the Debye temperature θ_D = 320 K were derived. This small value shows that YbNi_4Si cannot be classified as a heavy fermion system. These studies are completed by magnetic susceptibility, X-ray photoemission spectroscopy, and electrical resistivity.
16
Content available remote

Magnetic Properties and Magnetocaloric Effect of DyNi_{4}Si

71%
Synoradzki K., Kowalski W., Falkowski M., Toliński T., Kowalczyk A.
|
|
vol. 126
|
issue 1
162-163
EN
The magnetic properties and magnetocaloric effect (MCE) in DyNi_{4}Si have been studied by the magnetization and specific heat measurements. The saturation magnetic moment in μ_{0}H=9 T is equal to 7.9 μ_{B}/f.u at 4.2 K. A significant MCE has been observed around the second order phase transition at T_{C}=11 K. The maximum magnetic entropy change is -Δ S_{M}=14.5 J kg^{-1}K^{-1} for the magnetic field change of 9 T.
17
Content available remote

X-Ray Magnetic Circular Dichroism Studies on CeNi_4B

71%
Toliński T., Cezar J., Wende H., Kowalczyk A., Baberschke K.
Acta Physica Polonica A
|
2009
|
vol. 115
|
issue 1
129-131
EN
The CeNi_4B compound is a mixed-valence system. It is a paramagnet with μ_{eff}= 0.52 μ_{B}/f.u. and the paramagnetic Curie temperature θ= -10.7 K. In the present research we complete our previous magnetic susceptibility and X-ray photoemission measurements with new studies by the X-ray magnetic circular dichroism method. The observation of the Ce M_{4,5} edges carried out with X-ray magnetic circular dichroism confirms the mixed-valence state deduced previously from X-ray photoemission spectroscopy. Moreover, we report on the measurements of the Ni L_{2,3} edges, which enable verification of the Ni contribution to the magnetism of this compound.
18
Content available remote

Interlayer Exchange Coupling and Proximity Effect in V-Fe Multilayers

71%
Marczyńska A., Synoradzki K., Pugaczowa-Michalska M., Toliński T., Smardz L.
Acta Physica Polonica A
|
2018
|
vol. 133
|
issue 3
597-600
EN
We have studied interlayer exchange coupling (IEC) in (110) oriented V/Fe multilayers with ultrathin sublayers up to 7 monolayers (ML). Results showed that IEC energy depends on both vanadium and iron layer thicknesses. The local maxima of the antiferromagnetic coupling were found for V(7 ML)/Fe(4 ML) and V(3 ML)/Fe(3 ML) multilayers (MLs). The strongest AFM coupling energy of about 1.0 mJ/m² was measured at 5 K for the V(7 ML)/Fe(4 ML) multilayer. The position of the AFM peak for V(X ML)/Fe(3 ML) MLs near 3 ML of V spacer was also revealed by ab-initio calculations. Furthermore, theoretical calculations show an induced negative magnetic moment on V atoms near the V-Fe and Fe-V interfaces due to the proximity effect.
19
Content available remote

Valence Band and Core Levels of Ce_5Ni_2Si_3 Crystal Studied by X-ray Photoemission Spectroscopy

71%
Toliński T., Kowalczyk A., Chełkowska G., Mihalik M., Timko M.
Acta Physica Polonica A
|
2008
|
vol. 113
|
issue 1
327-330
EN
The crystal of Ce_5Ni_2Si_3 was prepared by the Czochralski method. The X-ray photoemission spectroscopy was measured for the valence band and the core levels. Based on the Ce(3d) doublet and its satellites a small value of the hybridization parameter of the f-states with the conduction electrons Δ=4 meV and the f-occupancy n_f close to 1 were found. X-ray photoemission spectroscopy shows that the region between 0 and 3 eV is predominated by the Ni(3d) and Ce(4f) peaks. Some features of the multiplet structure of the Ce(4f) states are also visible close to the Fermi level.
20
Content available remote

Low Temperature Properties of the Ce_{1-x}La_{x}NiAl_4

62%
Toliński T., Kowalczyk A., Reiffers M., Šebek J., Šantavá E., Curlik I., Ilkovič S.
|
|
issue 5
933-935
EN
Measurements of the heat capacity in ultralow temperatures (down to 350 mK) have been carried out for Ce_{1-x}La_{x}NiAl_4. The paramagnetic behavior above about 30 K can be well described by the Curie-Weiss magnetic susceptibility. The undoped CeNiAl_4 compound is a known heavy fermion system with a large electronic specific heat coefficient (γ = 0.5 J mol^{-1} K^{-2}) and the Kondo temperature in the range 30-80 K. In the case of the Ce_{0.8}La_{0.2}NiAl_4 and Ce_{0.6}La_{0.4}NiAl_4 compounds a peak in C/T appears below 2 K, which is strongly damped by the magnetic field. It is probably connected with the Kondo and/or magnetic interactions and the electronic specific heat coefficient is 0.19 J mol^{-1} K^{-2} (0.43 J mol^{-1} K^{-2}) for x = 0.2 (x = 0.4) at T → 0. The value determined above the peak, at temperature for which the magnetic field starts to decrease γ ( ≈ 3 K), is about 0.5 J mol^{-1} K^{-2} and the effect of the magnetic field can be well analyzed in frames of the single-ion Kondo model.
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.