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Wyświetlanie 1-15 z 17
Tytuł:
Fabrication and Study of the Organic-Inorganic Semiconductor Diodes Formed on n-Si
Autorzy:
Vengalis, B.
Šliužienė, K.
Lisauskas, V.
Grigaliūnaitė-Vonsevičienė, G.
Butkutė, R.
Lygaitis, R.
Gražulevičius, J.
Powiązania:
https://bibliotekanauki.pl/articles/1506270.pdf
Data publikacji:
2011-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.61.Ph
73.40.Lq
73.40.Ei
73.40.Ns
Opis:
We report fabrication and electrical characterization of the organic-inorganic semiconductor diode structures formed by evaporating thin films of three novel low molecular mass organic compounds on n-type Si substrates. The organic compounds containing carbazole and triphenylamine structural units, namely: 9,9'-bis(4-butylphenyl)-3,3'-bicarbazolyl (BPBC), 4-(1H-perimidin-2-yl)-N,N-diphenylbenzenamine (PER) and 9,9'-diethyl-3,3'-bicarbazolyl (EBC) have been synthesized. The current-voltage characteristics of the Au/(BPBC, EBC, PER)/n-Si diode structures measured at T = 295 K revealed rectifying behavior with a potential barrier height values of 0.71 eV, 0.73 eV, 0.76 eV, respectively.
Źródło:
Acta Physica Polonica A; 2011, 119, 2; 262-264
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetoresistive Properties of Manganite-Based Heterojunctions
Autorzy:
Devenson, J.
Vengalis, B.
Lisauskas, V.
Oginskis, A.
Anisimovas, F.
Ašmontas, S.
Powiązania:
https://bibliotekanauki.pl/articles/1807945.pdf
Data publikacji:
2009-06
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.70.-i
71.30.+h
73.50.-h
Opis:
Hole-doped $La_{2/3}Ba_{1/3}MnO_{3}$ (LBaMO), $La_{2/3}Ca_{1/3}MnO_{3}$ (LCaMO) and $La_{2/3}Ce_{1/3}MnO_{3}$ (LCeMO) thin films were grown heteroepitaxially on 0.1 wt.% Nb-doped $SrTiO_{3}(100)$ (STON) substrates by magnetron sputtering. The prepared LBaMO/STON, LCaMO/STON, LCeMO/STON heterostructures demonstrated nonlinear rectifying current-voltage characteristics. Negative magnetorestance values have been indicated at low bias, meanwhile bias-dependent magnetoresistance has been measured at positive bias voltage values U > U_d where U_d is the interfacial potential, corresponding to a steep current increase at a forward bias.
Źródło:
Acta Physica Polonica A; 2009, 115, 6; 1130-1132
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth and Investigation of $p-La_{2//3}Ca_{1//3}MnO_3$/n-Si Heterostructures
Autorzy:
Anisimovas, F.
Butkutė, R.
Devenson, J.
Maneikis, A.
Stankevič, V.
Pyragas, V.
Vengalis, B.
Powiązania:
https://bibliotekanauki.pl/articles/1813391.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.30.+h
73.43.Qt
75.47.Lx
81.15.Fg
Opis:
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.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 997-1000
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Growth and Investigation of Heterostructures Based on Multiferroic $BiFeO_3$
Autorzy:
Vengalis, B.
Devenson, J.
Oginskis, A.
Butkutė, R.
Maneikis, A.
Steikūnienė, A.
Dapkus, L.
Banys, J.
Kinka, M.
Powiązania:
https://bibliotekanauki.pl/articles/1813484.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
71.30.+h
73.43.Qt
75.47.Lx
Opis:
We report heteroepitaxial growth of multiferroic $BiFeO_3$ thin films by RF magnetron sputtering on lattice-matched $SrTiO_3$ substrates, as well as preparation and electrical properties of the heterostructures formed by growing $BiFeO_3$ thin films on highly conductive $LaNiO_3$ films and n-Si substrates. Nonlinear and rectifying current-voltage (I-U) characteristics were revealed for the heterojunctions in a wide temperature range (T=78-300 K).
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 1095-1098
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Reversible Resistive Switching in Electrically Nonhomogeneous $La_{0.67}Ca_{0.33}MnO_3$ Thin Films by Short Electrical Pulses
Autorzy:
Lučun, A.
Kiprijanovič, O.
Ašmontas, S.
Anisimovas, F.
Maneikis, A.
Sužied.lis, A.
Vengalis, B.
Powiązania:
https://bibliotekanauki.pl/articles/1813407.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Gk
75.47.Lx
07.57.Kp
Opis:
Resistance changes in thin electrically nonhomogeneous $La_{0.67}Ca_{0.33}MnO_3$ films were investigated using electrical pulses of nanosecond duration in the 80-300 K temperature range. Two types of reversible switching to higher resistive states with different starting temperature induced by series of the positive pulses were observed. Possible mechanisms of the resistance switching by short electrical pulses in the vicinity of $T_m$ and at 80-90 K are discussed.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 1059-1062
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Study of p-Fe₃O₄/n-(GaAs,Si) Heterostructures: Fabrication and Physical Properties
Autorzy:
Lisauskas, V.
Butkutė, R.
Vengalis, B.
Šliužienė, K.
Tamulevicius, S.
Andrulevicius, M.
Powiązania:
https://bibliotekanauki.pl/articles/1813406.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.40.-c
73.40.Gk
81.15.Cd
Opis:
We report preparation and investigation of p -n heterostructures based on Fe₃O₄ thin films grown on semiconductor Si and GaAs substrates. Fe₃O₄ films with thickness ranging from 60 to 300 nm were grown at 350÷450°C using dc magnetron sputtering technique. The measurement of X-ray diffraction and reflection high energy electron diffraction revealed polycrystalline microstructure of thin Fe₃O₄ films deposited on both Si and GaAs substrate. Investigation of surface composition by X-ray photoelectron spectroscopy showed that Fe 2p peak consists of three main peaks, namely, metallic iron Fe(0), Fe(II), and Fe(III). Transport measurements of Fe₃O₄/n-(Si, GaAs) heterostructures demonstrated nonlinear current-voltage (I -V) dependences in the temperature range from 300 K to 78 K.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 1055-1058
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Valence States of Metal Ions in $La_{0.7}Ce_{0.3}MnO_3$ Thin Films
Autorzy:
Mickevičius, S.
Bondarenka, V.
Grebinskij, S.
Oginskis, A.
Butkutė, R.
Tvardauskas, H.
Vengalis, B.
Orlowski, B.
Osinniy, V.
Pietrzyk, M.
Drube, W.
Powiązania:
https://bibliotekanauki.pl/articles/1813469.pdf
Data publikacji:
2008-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
79.60.-i
71.20.Nr
71.20.Eh
Opis:
We report valence states of ions in $La_{0.7}Ce_{0.3}MnO_3$ thin films grown by a reactive dc magnetron sputtering. The measurements were performed by means of high-energy X-ray photoelectron spectroscopy using synchrotron radiation. It was found that Ce ion in the compound is either in tetravalent or trivalent chemical state, manganese is in divalent, trivalent and tetravalent states, while La ion existing in oxide and hydroxide chemical species is in trivalent state.
Źródło:
Acta Physica Polonica A; 2008, 113, 3; 1071-1074
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electroresistance of Electrically Nonhomogeneous La$\text{}_{0.67}$Ca$\text{}_{0.33}$MnO$\text{}_{3}$/MgO Thin Films
Autorzy:
Kiprijanovič, O.
Lučun, A.
Ašmontas, S.
Anisimovas, F.
Butkutė, R.
Maneikis, A.
Sužiedėlis, A.
Vengalis, B.
Powiązania:
https://bibliotekanauki.pl/articles/2047239.pdf
Data publikacji:
2007-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.50.Gr
73.50.Lw
73.63.Bd
Opis:
Current and electrical field-induced electroresistive effects were investigated for La$\text{}_{0.67}$Ca$\text{}_{0.33}$MnO$\text{}_{3}$/MgO thin films demonstrating nanosized electrical inhomogeneities. Two different models based on enhanced conductivity of intergrain boundaries by injecting spin-polarized carriers from ferromagnetic grains and electrical field-enhanced hopping of carriers in high resistance intergrain media were carried out to explain nonlinear electrical properties of the films.
Źródło:
Acta Physica Polonica A; 2007, 111, 1; 141-146
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetoresistance of Polycrystalline La$\text{}_{0.7}$Ca$\text{}_{0.3}$MnO$\text{}_{3}$ Films in a Microwave Magnetic Field
Autorzy:
Lučun, A.
Butkutė, R.
Maneikis, A.
Kiprijanovič, O.
Anisimovas, F.
Gradauskas, J.
Sužiedėlis, A.
Vengalis, B.
Kancleris, Ž.
Ašmontas, S.
Powiązania:
https://bibliotekanauki.pl/articles/2047240.pdf
Data publikacji:
2007-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Gk
75.47.Lx
07.57.Kp
Opis:
We present new experimental evidence indicating the importance of magnetic field component of microwave field (f=9.4 GHz) for magnetoresistive properties of polycrystalline La$\text{}_{0.7}$Ca$\text{}_{0.3}$MnO$\text{}_{3}$ films. The microwave measurements revealed a different character of the temperature-dependent electrical resistance of polycrystalline La$\text{}_{0.7}$Ca$\text{}_{0.3}$MnO$\text{}_{3}$ films placed in the centre (maximal amplitude of H$\text{}_{10}$ wave vector) and at a narrow wall of the wave-guide (reduced H$\text{}_{10}$ amplitude). Theoretical estimations of the influence of substrate onto distribution of microwave electric and magnetic fields in the waveguide were performed using the finite-difference time-domain method.
Źródło:
Acta Physica Polonica A; 2007, 111, 1; 147-152
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Electrical Properties of La-Pr-Mn-O Thin Films and Heterostructures
Autorzy:
Butkutė, R.
Anisimovas, F.
Oginskis, A. K.
Steikūnienė, A.
Devenson, J.
Vengalis, B.
Powiązania:
https://bibliotekanauki.pl/articles/2047223.pdf
Data publikacji:
2007-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.70.-i
71.30.+h
73.50.-h
75.70.Pa
Opis:
In this paper we report the results of synthesis and study of both ceramic samples and thin films of electronically doped La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$ and related heterostructures composed of La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$ and p-type La$\text{}_{0.67}$Ca$\text{}_{0.33}$MnO$\text{}_{3}$. The ceramic La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$ samples were prepared by a conventional solid state reaction technique. Single phase La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$ thin films and La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$/La$\text{}_{0.67}$ Ca$\text{}_{0.33}$MnO$\text{}_{3}$ heterostructures were grown on lattice-matched perovskite NdGaO$\text{}_{3}$ substrates by pulsed laser deposition. Electron doping was indicated both for ceramic La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$ samples and thin films from thermopower data. Both ceramic samples and thin films of La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$ demonstrated resistivity of about 10 mΩ cm at 300 K and semiconductor-like resistance vs. temperature behavior with cooling down to 78 K. Meanwhile, the resistance of the La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$/La$\text{}_{0.67}$Ca$\text{}_{0.33}$MnO$\text{}_{3}$ interface showed an anomalous peak at 185 K. A series of post-deposition annealing experiments demonstrated a crucial role of annealing temperature and ambience on both electrical and magnetic properties of La$\text{}_{0.7}$Pr$\text{}_{0.3}$MnO$\text{}_{3}$ material and the heterostructures.
Źródło:
Acta Physica Polonica A; 2007, 111, 1; 111-115
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Surface Hydro-Oxidation of LaNiO$\text{}_{3-x}$ Thin Films
Autorzy:
Mickevičius, S.
Grebinskij, S.
Bondarenka, V.
Lisauskas, V.
Šliužienė, K.
Tvardauskas, H.
Vengalis, B.
Orłowski, B. A.
Osinniy, V.
Drube, W.
Powiązania:
https://bibliotekanauki.pl/articles/2047365.pdf
Data publikacji:
2007-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
79.60.-i
71.20.Nr
29.20.Lq
Opis:
The high-energy X-ray photoelectron spectroscopy was used to determine the composition and chemical structure of epitaxial LaNiO$\text{}_{3-x}$ films obtained by a reactive dc magnetron sputtering. It was found that the oxide and hydroxide species of La and Ni are on the films surface. The thickness of hydroxide enriched layer, estimated from the oxide and hydroxide peak intensities, is about 2 nm.
Źródło:
Acta Physica Polonica A; 2007, 112, 1; 113-120
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Response of Grained La$\text{}_{0.67}$Ca$\text{}_{0.33}$MnO$\text{}_{3}$ Films to Microwave Radiation and the Method for Measuring Electrical Resistance of Grains
Autorzy:
Repšas, K.
Laurinavičius, A.
Vaškevičius, R.-A.
Anisimovas, F.
Deksnys, A.
Vengalis, B.
Powiązania:
https://bibliotekanauki.pl/articles/2047104.pdf
Data publikacji:
2006-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Lx
75.47.De
Opis:
It was found that the response of grained La$\text{}_{0.67}$Ca$\text{}_{0.33}$MnO$\text{}_{3}$ films to microwave radiation is of thermal nature. A nonresonant method for measuring of the electric resistance of grains was developed. It allows one to avoid the influence of the magnetic field of the wave on the measurement results. The measurements of the temperature dependences of the grain electric resistance indicate that in the vicinity of the maximum-resistance temperature T$\text{}_{m}$, the intrinsic electric resistance of the grains is more than by two orders of magnitude lower than the film resistance measured by applying the dc current. The obtained experimental results agree well with those given by resonant techniques.
Źródło:
Acta Physica Polonica A; 2006, 110, 4; 537-544
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Frequency Dependence of Electrical Response of Polycrystalline LCMO Thin Films
Autorzy:
Ašmontas, S.
Anisimovas, F.
Balevičius, S.
Cimmperman, P.
Gradauskas, J.
Lučun, A.
Stankevič, V.
Sužiedėlis, A.
Vengalis, B.
Žurauskienė, N.
Powiązania:
https://bibliotekanauki.pl/articles/2041721.pdf
Data publikacji:
2005-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
75.47.Gk
75.47.Lx
07.57.Kp
Opis:
Influence of strong electric field in wide frequency range (from DC to 35 GHz) on electrical resistance of thin La$\text{}_{0.67}$Ca$\text{}_{0.33}$MnO$\text{}_{3}$ 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.
Źródło:
Acta Physica Polonica A; 2005, 107, 1; 193-197
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Investigation of Heterostructure Formed from Hole- and Electron-Doped Lanthanum Manganites
Autorzy:
Vengalis, B.
Rosa, A. M.
Devenson, J.
Šliužienė, K.
Lisauskas, V.
Oginskis, A.
Anisimovas, F.
Pyragas, V.
Powiązania:
https://bibliotekanauki.pl/articles/2041760.pdf
Data publikacji:
2005-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
73.40.Cg
73.40.Lg
75.50.Dd
Opis:
High crystalline quality films of n-La$\text{}_{2}\text{}_{/}\text{}_{3}$ Ce$\text{}_{1}\text{}_{/}\text{}_{3}$ MnO$\text{}_{3}$, p-La$\text{}_{2}\text{}_{/}\text{}_{3}$ Ca$\text{}_{1}\text{}_{/}\text{}_{3}$ MnO$\text{}_{3}$ and related p-n diode structures were grown heteroepitaxially on lattice-matched SrTiO$\text{}_{3}$(100) substrates by dc magnetron sputtering and pulsed laser deposition. The La$\text{}_{2}\text{}_{/}\text{}_{3}$ Ce$\text{}_{1}\text{}_{/}\text{}_{3}$ Mn O$\text{}_{3}$/La$\text{}_{2}\text{}_{/}\text{}_{3}$ Ca$\text{}_{1}\text{}_{/}\text{}_{3}$ MnO$\text{}_{3}$ bilayer was patterned into a strip-like geometry to investigate electrical properties of the interface. Significant magnetoresistance values and nonlinear current-voltage characteristics were indicated for the interface of the p-n diode heterostructure.
Źródło:
Acta Physica Polonica A; 2005, 107, 2; 290-293
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Spin-Polarized Carrier Injection in MOCVD-Grown YBCO/STO/LSMO Heterostructures with Underlying YBCO Layer
Autorzy:
Vengalis, B.
Plaušinaitiene, V.
Abrutis, A.
Šaltytė, Z.
Powiązania:
https://bibliotekanauki.pl/articles/2041755.pdf
Data publikacji:
2005-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.50.+r
81.15.Gh
85.25.-j
Opis:
The oxide heterostructures composed of superconducting YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7}$ bottom layer, the overlying ferromagnetic La$\text{}_{1-x}$Sr$\text{}_{x}$MnO$\text{}_{3}$ film and SrTiO$\text{}_{3}$ as ultrathin (d≈5 nm) barrier were grown heteroepitaxially onto LaAlO $\text{}_{3}$ substrates by applying pulsed liquid injection metalorganic chemical vapour deposition technique. We report anomalous interface resistance increase with cooling just below superconductive transition temperature (T$\text{}_{c}$≅85 K) and enhanced suppression of supercurrent of strip-like YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7}$ film due to spin-polarized carriers injected from the ferromagnetic manganite layer.
Źródło:
Acta Physica Polonica A; 2005, 107, 2; 286-289
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
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