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1

Growth and Investigation of p-La_{2/3}Ca_{1/3}MnO_3/n-Si Heterostructures

100%

Anisimovas F., Butkutė R., Devenson J., Maneikis A., Stankevič V., Pyragas V., Vengalis B.

Acta Physica Polonica A

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2008

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vol. 113

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issue 3

997-1000

EN

We report the fabrication and investigation of p-n diode structures based on thin hole-doped La_{2/3}Ca_{1/3}MnO_3 films grown on n-type silicon substrates. La_{2/3}Ca_{1/3}MnO_3 films with typical thickness of about 400 nm were prepared using pulsed laser deposition. Reflection high-energy electron diffraction measurements revealed polycrystalline quality of La_{2/3}Ca_{1/3}MnO_3 thin films on Si substrates. The surface roughness of La_{2/3}Ca_{1/3}MnO_3 films investigated by atomic force microscopy was found to be in the range of 25÷30 nm. Studies of electrical properties showed that La_{2/3}Ca_{1/3}MnO_3/Si heterostructures exhibit nonlinear asymmetric I-V characteristics both at room temperature and at 78 K. Furthemore, it was shown that these I-V dependences are sensitive to magnetic field, especially at lower voltages.

2

High Pulsed Magnetic Field Sensor Based on La-Ca-Mn-O Thin Polycrystalline Films

100%

Balevičius S., Žurauskienė N., Stankevič V., Keršulis S., Novickij J., Altgilbers L., Clarke F.

Acta Physica Polonica A

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2005

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vol. 107

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issue 1

207-210

EN

It is demonstrated that polycrystalline La_{0.33}Ca_{0.67}MnO_3 thin film sensors can be used to measure pulsed strong magnetic fields with microsecond duration rise and decay times. The response characteristics of these sensors were investigated using 0.7-1.0 ms duration bell-shaped magnetic field pulses of 10-20 T amplitudes and by using special waveform magnetic field pulses with amplitudes of 40 T and decay times of 50μs. The response of these magnetic field sensors was compared with those of conventional loop sensors and Faraday rotation sensors using Bi_{12}SiO_{20} single crystals as a known standard.

3

Measurement of the Magnetic Field Distribution in Railguns Using CMR-B-Scalar Sensors

100%

Liebfried O., Schneider M., Loeffler M., Balevičius S., Žurauskienė N., Stankevič V.

Acta Physica Polonica A

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2009

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vol. 115

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issue 6

1125-1127

EN

Colossal magnetoresistance effect B-scalar magnetic field sensors with effective areas of 0.05 mm^2 were used very close to the rails for magnetic field measurements. These measurements were performed during static and dynamic railgun experiments. In static experiments three different rail materials were used and the results are compared to a finite element simulation.

4

Influence of Sr Content on CMR Effect in Polycrystalline La_{1-x}Sr_{x}MnO_{3} Thin Films

100%

Žurauskienė N., Balevičius S., Stankevič V., Paršeliūnas J., Keršulis S., Abrutis A., Plaušinaitienė V.

Acta Physica Polonica A

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2009

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vol. 115

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issue 6

1136-1138

EN

The magnetoresistance of thin polycrystalline La_{1-x}Sr_{x}MnO_{3} films deposited on lucalox substrate using metal organic chemical vapor deposition technique was investigated in pulsed magnetic fields up to 18 T in the temperature range 100-320 K. The influence of film preparation conditions, ambient temperature variation and Sr content is analyzed in order to determine the optimal conditions for the design of CMR-B-scalar magnetic field sensor based on thin manganite film, operating at room temperature.

5

Magneto- and Electroresistance of Ultrathin Anisotropically Strained La-Sr-MnO Films

84%

Balevičius S., Stankevič V., Žurauskienė N., Šimkevičius Č., Paršeliūnas J., Cimmperman P., Abrutis A., Plaušinaitienė V.

Acta Physica Polonica A

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2005

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vol. 107

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issue 1

203-206

EN

The magnetoresistance anisotropy of ultrathin La_{0.83}Sr_{0.17}Mn O_3 films deposited on NdGaO_3 substrate by metalorganic chemical vapour deposition technique was investigated. The electric-field-induced resistance change was studied up to electric fields of 10 kV/cm using ns duration electrical pulses. It was found that in ultrathin (< 10 nm) and thin (< 50 nm) films the origin of electric-field-induced resistance change is thermal. However, the films with thicknesses of about 20 nm, exhibit negative electric-field-induced resistance change, having a pure electronic nature. This effect is explained in terms of two-layer systems with imperfections located at the interface between the layers.

6

Frequency Dependence of Electrical Response of Polycrystalline LCMO Thin Films

84%

Ašmontas S., Anisimovas F., Balevičius S., Cimmperman P., Gradauskas J., Lučun A., Stankevič V., Sužiedėlis A., Vengalis B., Žurauskienė N.

Acta Physica Polonica A

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2005

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vol. 107

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issue 1

193-197

EN

Influence of strong electric field in wide frequency range (from DC to 35 GHz) on electrical resistance of thin La_{0.67}Ca_{0.33}MnO_3 polycrystalline manganite films was investigated in the range of (78÷300) K. Different behavior of resistance change vs. temperature was observed when pulsed DC electric field and microwaves were applied to the films. When pulsed DC electric field is applied the electric-field-induced resistance change ("electroresistance") of manganite film depended nearly monotonically on temperature. However, in microwave electric fields a non-monotonic character of the electroresistance temperature dependence was observed. The dependence of the electroresistance on quality of manganite films was observed in case of microwaves. The experimental findings are explained assuming different electrical current mechanisms in case of DC and microwave fields. The applied voltage drops mainly across the grains of polycrystalline film due to a presence of displacement currents in case of microwaves, whereas in DC case the voltage drop is across the grain boundaries.

7

Electroresistance of La-Ca-MnO Thin Films

84%

Cimmperman P., Stankevič V., Žurauskienė N., Balevičius S., Anisimovas F., Paršeliūnas J., Kiprijanovič O., Altgilbers L.

Acta Physica Polonica A

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2004

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vol. 105

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issue 1-2

107-114

EN

Epitaxial, textured, and polycrystalline La_{0.7}Ca_{0.3}Mn O_3 films, having about 150 nm thickness, were prepared by pulsed laser deposition techniques onto (110) NdGaO_3, MgO and lucalox substrates and investigated using 10 ns duration, 0.5 ns rise time electrical pulses having amplitude up to 500 V. Electroresistance of the films [R(E)-R(0)]/R(0) was investigated up to 80 kV/cm electric field strengths in temperatures ranging from 300 K to 4.2 K. Strong (up to 93%) negative electroresistance was obtained in polycrystalline La_{0.7}Ca_{0.3}MnO_3 films prepared on MgO and lucalox substrates. The epitaxial films grown on NdGaO_3 substrate demonstrated only a small resistance change due to Joule heating induced by a current pulse. It was concluded that electroresistance manifests itself in strongly inhomogeneous manganites films exhibiting a large number of structural imperfections producing ferromagnetic tunnel junction nets.

8

Fast Electrical Switching of Thin Manganite Films

84%

Balevičius S., Kiprijanovič O., Stankevič V., Žurauskienė N., Česnys A., Tolvaišienė S., Abrutis A., Plaušinaitienė V.

Acta Physica Polonica A

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2008

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vol. 113

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issue 3

821-824

EN

The effects of strong pulsed electric field on the electrical properties of thin epitaxial La_{0.7}Sr_{0.3}MnO_3 films were investigated. The fast electrical switching from high resistance off-state to low resistance on-state was obtained at current densities higher than 10^6 A/cm^2. This current was able to induce an irreversible damage of the sample in the regions at the edges of the electrodes of the film. It was demonstrated that thermal effects are responsible for appearance of delay time and asymmetrical shape of current channel in on-state, however, the fast switching from off- to on-state is a result of electronic effects appearing when critical power is reached in the film.

9

Thin Film Manganite-Metal Interconnection and "Loop Effect" Studies in CMR-Based High Magnetic Field Sensors

84%

Balevičius S., Stankevič V., Žurauskienė N., Šimkevičius Č., Liebfried O., Löffler M., Schneider M., Abrutis A., Plaušinaitienė V.

Acta Physica Polonica A

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2009

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vol. 115

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issue 6

1133-1135

EN

The design, technology and main characteristics of Ag contacts as well as "loop effect" peculiarities of colossal magnetoresistance B-scalar high magnetic field sensor based on La_{1-x}(Ca)Sr_x MnO_3 films used for measuring high magnetic field pulses are presented.

10

Electron Transport in Modulation-Doped InAlAs/InGaAs/InAlAs Heterostructures in High Electric Fields

69%

Požela K., Požela J., Jucienė V., Vasil'evskii I., Galiev G., Klimov E., Sužiedėlis A., Žurauskienė N., Stankevič V., Keršulis S., Paškevič Č.

Acta Physica Polonica A

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2011

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vol. 119

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issue 2

170-172

EN

The following peculiarities of electron transport in In_{0.53}Ga_{0.47}As/In_{0.52}Al_{0.48}As quantum wells with δ-Si-doped In_{0.52}Al_{0.48}As barriers at high electric fields are discovered: (1) an enhancement of electron mobility by inserting the InAs phonon wall into the In_{0.53}Ga_{0.47}As/In_{0.52}Al_{0.48}As quantum well, as well as increasing the InAs content in the modulation-doped In_{0.8}Ga_{0.2}As/In_{0.7}Al_{0.3}As heterostructure; (2) a large decrease in electron mobility and a change of electron density with increasing electric field in the range of 1-4 kV/cm; (3) a magnetic field dependence of the threshold electric field for intervalley scattering of electrons; and (4) microwave current oscillations in high electric fields.

Refine search results

Growth and Investigation of p-La_{2/3}Ca_{1/3}MnO_3/n-Si Heterostructures

High Pulsed Magnetic Field Sensor Based on La-Ca-Mn-O Thin Polycrystalline Films

Measurement of the Magnetic Field Distribution in Railguns Using CMR-B-Scalar Sensors

Influence of Sr Content on CMR Effect in Polycrystalline La_{1-x}Sr_{x}MnO_{3} Thin Films

Magneto- and Electroresistance of Ultrathin Anisotropically Strained La-Sr-MnO Films

Frequency Dependence of Electrical Response of Polycrystalline LCMO Thin Films

Electroresistance of La-Ca-MnO Thin Films

Fast Electrical Switching of Thin Manganite Films

Thin Film Manganite-Metal Interconnection and "Loop Effect" Studies in CMR-Based High Magnetic Field Sensors

Electron Transport in Modulation-Doped InAlAs/InGaAs/InAlAs Heterostructures in High Electric Fields