Wszystkie pola: Krok, T. - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: High Spin-Low Spin Transitions in $Cu_{0.2}Co_{0.76}Cr_{1.83}Se_4$ Semiconductor
Autorzy:: Maciążek, E.
Groń, T.
Pacyna, A.
Mydlarz, T.
Krok-Kowalski, J.
Powiązania:: https://bibliotekanauki.pl/articles/1489908.pdf
Data publikacji:: 2012-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Wx
75.50.Dd
75.50.Ee
Opis:: Magnetization, ac and dc magnetic susceptibility measured in the zero-field-cooled mode were used to study the high spin-low spin transitions in polycrystalline $Cu_{0.2}Co_{0.76}Cr_{1.83}Se_4$ semiconductor. The real part component of fundamental susceptibility $χ_1^\prime$ (T) and its second $(χ_2)$ and third $(χ_3)$ harmonics revealed two spectacular peaks at 128 K and at 147 K, confirming the appearance of the spin-crossover phenomenon.
Źródło:: Acta Physica Polonica A; 2012, 121, 3; 687-689
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 2.

Tytuł:: Spin Crossover in Cu$\text{}_{x}$Co$\text{}_{y}$Cr$\text{}_{z}$Se$\text{}_{4}$ Semiconductors
Autorzy:: Maciążek, E.
Groń, T.
Pacyna, A. W.
Mydlarz, T.
Zawisza, B.
Krok-Kowalski, J.
Powiązania:: https://bibliotekanauki.pl/articles/2048134.pdf
Data publikacji:: 2011-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Wx
75.50.Dd
75.50.Ee
Opis:: Magnetization and magnetic susceptibility measured in the zero-field-cooled mode were used to study the spin crossover transition in polycrystalline Cu$\text{}_{x}$Co$\text{}_{y}$Cr$\text{}_{z}$Se$\text{}_{4}$ compounds. With increasing Co content a transition from ferromagnetic order via ferrimagnetic one to antiferromagnetic-like behaviour was observed. This transition is accompanied with a lowering symmetry from cubic to monoclinic and for the latter the spin crossover phenomenon occurs. These results are considered in a framework of the ligand-field split and the spin-orbit coupling.
Źródło:: Acta Physica Polonica A; 2011, 119, 5; 711-713
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 3.

Tytuł:: Electrical and Magnetic Studies of the $Cd_{x}Cr_{y}V_{z}Se_{4}$ Spinels
Autorzy:: Groń, T.
Duda, H.
Malicka, E.
Zawisza, B.
Krok-Kowalski, J.
Pacyna, A.
Powiązania:: https://bibliotekanauki.pl/articles/1791407.pdf
Data publikacji:: 2009-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Jc
75.50.Pp
75.50.Dd
Opis:: The electrical and magnetic investigations carried out on the polycrystalline spinels with the general chemical formula $Cd_{x}Cr_{y}V_{z}Se_{4}$ (where z = 0.06, 0.12, 0.24, and 0.31) revealed semiconducting and ferromagnetic properties with a Curie temperature of 127.5 K. A step-like structure of the electrical conductivity, σ(T), was observed for the polycrystal containing 6% V ions in the octahedral sites while the remaining samples showed a typical Arrhenius behaviour of σ(T). These effects are interpreted in terms of ferromagnetic spin clusters which finally dissolve on going towards the paramagnetic limit including non-stoichiometry.
Źródło:: Acta Physica Polonica A; 2009, 116, 5; 969-970
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 4.

Tytuł:: Critical Behaviour of the Mean-Field Ferromagnet $Cu_{1.02}[Cr_{1.77}Ti_{0.24}]Se_4$
Autorzy:: Krok-Kowalski, J.
Władarz, G.
Rduch, P.
Malicka, E.
Groń, T.
Guzik, A.
Powiązania:: https://bibliotekanauki.pl/articles/1409626.pdf
Data publikacji:: 2012-12
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.40.Cx
75.50.Dd
64.60.Ht
Opis:: Magnetization, M, and susceptibility, χ, measurements showed both strong lowering of magnetic moment in comparison with $CuCr_2Se_4$ matrix and zero-field-cooling-field-cooling susceptibility splitting characteristic for the spin-glass behaviour. Isothermal magnetization curves, M(H), easy saturate and large values both of the Curie $T_{C}$=253 K and Curie-Weiss θ=283.5 K temperatures indicate the ferromagnetic order which coexists with the spin-glass state. The critical behaviour investigated around the paramagnetic-ferromagnetic phase transition revealed that the values of critical exponents are close to those predicted by the mean field model for long-range magnetic interactions.
Źródło:: Acta Physica Polonica A; 2012, 122, 6; 1102-1104
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 5.

Tytuł:: Hopkinson-Like Effect in Single-Crystalline $CdCr_2Se_4$ and $Cd[Cr_{1.89}Ti_{0.08}]Se_4$
Autorzy:: Malicka, E.
Groń, T.
Pacyna, A.
Duda, H.
Krok-Kowalski, J.
Powiązania:: https://bibliotekanauki.pl/articles/1489913.pdf
Data publikacji:: 2012-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Jc
75.50.Pp
75.50.Dd
Opis:: The static (dc) and dynamic (ac) magnetic measurements of $CdCr_2Se_4$ and $Cd[Cr_{1.89}Ti_{0.08}]Se_4$ showed their ferromagnetic properties with a Curie temperature $T_{C}$ ≈ 130 K and revealed on the real component of ac susceptibility curve, the peaks near $T_{C}$ at 200 Oe, 450 Oe and 1 kOe, characteristic for the Hopkinson ones. The meaningful reduction of saturation moment to 4.73 $μ_{B}$/f.u. for $Cd[Cr_{1.89}Ti_{0.08}]Se_4$ suggests the diamagnetic configuration of Ti ions, which dilutes the ferromagnetic sublattice of Cr ones and causes reducing of the energy losses visible on the imaginary components of ac susceptibility curve. Close for zero values of higher susceptibility harmonics above $T_{C}$ are pointing out to the lack of the spin fluctuations in the paramagnetic state.
Źródło:: Acta Physica Polonica A; 2012, 121, 3; 690-693
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Skocz do pozycji: 6.

Tytuł:: Mictomagnetic Order in Cd$\text{}_{0.87}$Cr$\text{}_{1.93}$V$\text{}_{0.06}$Se$\text{}_{4}$ Semiconductor
Autorzy:: Groń, T.
Malicka, E.
Zawisza, B.
Duda, H.
Krok-Kowalski, J.
Pacyna, A. W.
Powiązania:: https://bibliotekanauki.pl/articles/2048136.pdf
Data publikacji:: 2011-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Jc
75.50.Pp
75.50.Dd
Opis:: The complex ac dynamic magnetic susceptibility was used to study the mictomagnetic-like behavior in polycrystalline Cd$\text{}_{0.87}$Cr$\text{}_{1.93}$V$\text{}_{0.06}$Se$\text{}_{4}$ spinel. The temperature dependences of the zero field in-phase (real part) and out-of-phase (imaginary part) components of fundamental susceptibility measured at the oscillating field H$\text{}_{ac}$ = 0.5 Oe and at the constant frequency of 125 Hz are characteristic for the mictomagnetic order. These results well correlate with the anomalies in the second and third harmonics of the ac susceptibility indicating the cluster glass.
Źródło:: Acta Physica Polonica A; 2011, 119, 5; 714-716
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

Artykuł

Informacja