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1

Magnetic Properties of the RbNd(WO₄)₂ Single Crystal

100%

Borowiec M., Zubov E., Zajarniuk T., Barański M.

Acta Physica Polonica A

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2016

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vol. 129

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issue 3

359-361

EN

The magnetic investigations as a function of the temperature and magnetic field for the rubidium neodymium double tungstate RbNd(WO₄)₂ single crystal have been performed. The magnetization was measured in the temperature range from 4.2 to 100 K and for the magnetic field up to 1.5 T. The crystal field and exchange parameters were found.

2

Influence of Nonstoichiometry on Magnetocaloric Effect in (La_{0.7}Ca_{0.3})_{1 - x}Mn_{1+x}O_3

76%

Sazanovich A., Pietosa J., Pashchenko A., Zubov E., Dyakonov V., Szymczak H.

Acta Physica Polonica A

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2012

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vol. 122

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issue 1

162-166

EN

Magnetocaloric effect in (La_{0.7}Ca_{0.3})_{1 - x}Mn_{1 + x}O_3 manganites with x = 0, 0.1, 0.2 has been investigated. It is found a strong influence of nonstoichiometry caused by excessive manganese on the magnetic entropy change. The magnetocaloric effect was evaluated from the isothermal curves of spontaneous magnetization versus the applied magnetic field by using the well-known thermodynamical Maxwell relation. The maximum entropy value, | Δ S_{M}^{max} |, near the ferromagnetic-paramagnetic phase transition is shown to increase with the manganese content. The La_{0.56}Ca_{0.24}Mn_{1.2}O_3 manganite exhibits the largest | Δ S_{M}^{max} | value equal to 3.09 J kg^{-1} K^{-1} at 15 kOe near T_{C} = 267 K. The magnetocaloric effect values obtained allow to propose that the studied manganites are promising materials for future cooling application.

3

Magnetic Properties of the Nanocrystalline DyMnO_{3} Compound

64%

Dyakonov V., Szytuła A., Baran S., Kravchenko Z., Zubov E., Iessenchuk O., Bazela W., Dul M., Zarzycki A., Szymczak H.

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issue 4

607-610

EN

We report on the X-ray powder diffraction and magnetic measurements of the polycrystalline and the two nanocrystalline samples of DyMnO_{3} compound synthesized at temperatures of 800 and 850°C. All samples at room temperature crystallize in the orthorhombic crystal structure (space group Pnma). The crystal structure parameters determined change only slightly with preparation methods but the average grains size of the nanoparticles determined from X-ray data increases significantly with increasing annealing temperature. Temperature dependence of the magnetic susceptibility indicates the antiferromagnetic order in Dy sublattice at low temperatures.

4

Manifestation of Spin-Glass-Like Behavior in the Organometallic Magnet

64%

Dyakonov V., Arciszewska M., Dobrowolski W., Szewczyk A., Szymczak H., Aksymentieva E., Varyukhin V., Zubov E., Gutowska M.

Acta Physica Polonica A

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2000

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vol. 97

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issue 5

863-866

EN

Ac susceptibility (χ_{ac}) and dc magnetization (M_{dc}) of the organometallic magnet Na[FeO_{6}(C_{10}H_{8}N)_{3}] have been studied in temperature range of 4.2-200 K, in an external magnetic field up to 16 kOe. Some peculiarities of the χ_{ac} and M _{dc} behavior, which are characteristic of spin-glasses, e.g. cusps in the susceptibility and zero-field-cooled magnetization, an irreversibility between the field-cooled and zero-field-cooled magnetization and dependences of the T_{cusp} temperature on the frequency and the intensity of the magnetic field, were observed at low temperatures.

5

Structure and Transport Characteristics of Tunnel Junctions with Hybrid Semiconductor Barriers with Quantum Dots

64%

Shaternik V., Shapovalov A., Prikhna T., Suvorov O., Skorik M., Shaternik A., Bondarchuk V., Zubov E.

Acta Physica Polonica A

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2018

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vol. 133

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issue 4

1060-1064

EN

We propose to realize MoRe/SiO_x(W)/MoRe hybrid junctions by using self-organization effects for the creation of quantum dots (tungsten clusters) in the semiconductor barriers consisting of a mixture of silicon and silicon oxide. Current-voltage characteristics of the MoRe/SiO_x(W)/MoRe samples have been measured in a wide voltage range from -900 to 900 mV at temperatures from 4.2 to 77 K. At low temperatures and for a comparatively small W content in the hybrid barrier, the heterostructures exhibited current-voltage curves of an unusual shape. Single or several current peaks caused by electron tunneling through the allowed states in the barrier have been observed in the transport characteristics. With increasing temperature, superconducting fluctuations in the MoRe electrodes become unimportant, and the current-voltage curve of a heterostructure follows the Ohm law. At last, we present theoretical description of the charge transport in such inhomogeneous systems with account of many-electron processes.

6

Crystalline Structure of Potassium Holmium Double Tungstate

46%

Borowiec M., Dyakonov V., Woźniak K., Dobrzycki Ł., Majchrowski A., Michalski E., Zubov E., Khatsko E., Zayarnyuk T., Szewczyk A., Gutowska M., Rykova A., Barański M., Domukhovski V., Shtyrkhunova V., Iwanowski P., Żmija J., Szymczak H.

Acta Physica Polonica A

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2011

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vol. 119

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issue 6

835-837

EN

The potassium holmium double tungstate was prepared by using top seeded solution growth technique. Structural investigations have been performed at room temperature. The KHo(WO_4)_2 single crystal belongs to the monoclinic space group C2/c with the unit-cell parameters: a = 10.624(2) Å, b = 10.352(2) Å, c = 7.5434(15) Å, β = 130.78(3)^{o}, and Z = 4. The atomic coordinates, isotropic and anisotropic displacement parameters and interionic distances for the studied structure were determined.

Refine search results

Magnetic Properties of the RbNd(WO₄)₂ Single Crystal

Influence of Nonstoichiometry on Magnetocaloric Effect in (La_{0.7}Ca_{0.3})_{1 - x}Mn_{1+x}O_3

Magnetic Properties of the Nanocrystalline DyMnO_{3} Compound

Manifestation of Spin-Glass-Like Behavior in the Organometallic Magnet

Structure and Transport Characteristics of Tunnel Junctions with Hybrid Semiconductor Barriers with Quantum Dots

Crystalline Structure of Potassium Holmium Double Tungstate