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We report modification of electrical and magnetoresistive properties for the La2/3Sr1/3MnO3/MgO(100) thin films influenced by high power pulsed (  10 ns) laser radiation ( = 532 nm). SEM surface study revealed cracks extended along [100] directions and partially melted material at film surface with radiation power increasing. Low field magnetoresistance typical for high quality intergrain junctions has been measured at T < 240 K for the films with laser beam-induced cracks while partial melting of the material resulted increased electrical resistance, lowering of the paramagnetic to ferromagnetic transition temperature TC and reduced magnetoresistance values in the vicinity of TC. [ABSTRACT FROM AUTHOR]

Short rise time (200 ps) pulses were used for excitation of monopole antennas. They have 7 cm height, designed using fractal geometry and were attached to an open end of coaxial cable. Receiving antennas span bandwidth in 0.45-18 GHz range and 0- 18 GHz bandwidth sampling oscilloscope was used for visualization of received signals. Radiated signals have wide spectrum in 0.45-12.05 GHz frequency range and base B=464. This indicates on radiation of large bandwidth and long duration signals. [ABSTRACT FROM AUTHOR]

There were done investigations of TaN thin film absorbers which were damaged by ns duration high voltage electric pulses. Images of damaged absorbers were obtained using microscopes. There were observed damages with film melting and dendrite-like film destruction. It was proposed explanation of damaging regime by local overheating instability during rise time and following fast propagation of cracks accompanied by local crack branching. The obtained results can be applied for modern electronics. [ABSTRACT FROM AUTHOR]

Electroresistive properties of polycrystalline La0.67Ca0.33MnO3 thin films have been investigated in 80-300 K temperature range. Nanosecond electrical pulses were used to create electric field within the samples. The resistance of the films was strongly suppressed by the applied electric filed. The films are explained to be in a highly resistive state and strong resistance drop is attributed to the captured carrier release at the strained areas near grain and other boundaries. Possible influence of laser pulses on highly resistive state is also discussed. The obtained results stimulate further experiments including wideband optical illumination of the La0.67Ca0.33MnO3 films. [ABSTRACT FROM AUTHOR]

Nonhomogeneous thin La0.67Ca0.33MnO3 films were subjected to thermocycling procedures. Both pulsed thermocycling (nanosecond electrical pulse heating at 80 K) and LN thermocycling (quick cooling with liquid nitrogen and following slow heating up to 200 K) caused an appearance of highly resistive states in the films. Described different mechanisms stipulated the appearance in both cases. Analysis of changes of electrical properties induced by the thermocycling procedures shows that lattice structural changes as well as formation of mesoscopic objects within the films are responsible for unique behaviour of highly resistive states. [ABSTRACT FROM AUTHOR]

The pulse excitation of aperture antennas (2.5×2 cm²) with resistive covering by nanosecond electric pulses was used for irradiation of ultra-wideband electromagnetic pulses. Wideband rectangular horn antennas were used for receiving of the signals and wideband sampling oscilloscope was used for their visualisation. Obtained results indicate on possible usage of the irradiation for control thickness of resistive thin film, including nanostructured ones. Materials with nanostructured resistive covering may be used for creation of small sized ultra-wideband plane aperture antennas. [ABSTRACT FROM AUTHOR]

We report preparation and electrical properties of the p-n heterostructures formed by depositing La2⁄3Ca1⁄3MnO3 (LCMO) and La2⁄3Sr1⁄3MnO3 (LSMO) thin films on Nb-doped SrTiO3 substrates. The LCMO films were grown by pulsed laser deposition while pulsed injection metal-organic chemical vapour deposition was used for growth of LSMO films. Asymmetric I-V characteristics in respect to current direction were measured for the heterostructures both above and below the characteristic Curie temperature Tc. Hysteresis-like behaviour of the junction magnetoresistance with applied magnetic field was observed for the heterostructures below Tc. [ABSTRACT FROM AUTHOR]

The article investigates the electrical switching with memory effect in thin films. It was observed that the metastable high resistive states induced by direct current decreased under applied strong electric field in films with structural inhomogeneities. The surface analysis of cleaved magnesium oxide substrates using atomic force microscope (AFM) revealed terrace-like structures with height of the steps ranging from 5 to 35 millimicron.

Polycrystalline films of La0,67Ca0,33MnO3 with two various paramagnetic to ferromagnetic (PM-FM) transition temperatures (135 K and 200 K) demonstrating nanosized inhomogeneities were deposited on MgO substrates. Electrical properties of the films were investigated using stabilized dc and electrical pulses of nanosecond duration. A decrease of film resistance induced both by flowing dc and applied pulsed electric field was indicated. The observed resistance decrease in PM phase was associated with polaron hopping while that in FM phase was associated with current-induced polarization of insulating areas. [ABSTRACT FROM AUTHOR]

We report preparation and electrical properties of the p-n heterostructures formed by depositing La2/3Ca1/3MnO3 (LCMO) and La2/3Sr1/3MnO3 (LSMO) thin films on Nb-doped SrTiO3 substrates. The LCMO films were grown by pulsed laser deposition while pulsed injection metal-organic chemical vapour deposition was used for growth of LSMO films. Asymmetric I-V characteristics in respect to current direction were measured for the heterostructures both above and below the characteristic Curie temperature Tc. Hysteresis-like behaviour of the junction magnetoresistance with applied magnetic field was observed for the heterostructures below Tc. [ABSTRACT FROM AUTHOR]

Polycrystalline films of La0,67Ca0,33MnO3 with two various paramagnetic to ferromagnetic (PM-FM) transition temperatures (135 K and 200 K) demonstrating nanosized inhomogeneities were deposited on MgO substrates. Electrical properties of the films were investigated using stabilized dc and electrical pulses of nanosecond duration. A decrease of film resistance induced both by flowing dc and applied pulsed electric field was indicated. The observed resistance decrease in PM phase was associated with polaron hopping while that in FM phase was associated with current- induced polarization of insulating areas. [ABSTRACT FROM AUTHOR]