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A brief overview of the high-field facilities at the Vilnius High Magnetic Field Centre (VMC) is presented in this paper. We highlight the main activity of the VMC, which lies in studying the effects of pulsed magnetic and electrical fields on material properties, and give a short description of the pulsed magnets. A new method for generating nanosecond duration strong electric field pulse in conjunction with a magnetic field pulse is presented. The possibility of modulating electric field pulses by pulsed magnetic fields is discussed. Here, we also report on our investigations of the colossal magnetoresistance (CMR) effect in thin polycrystalline La-Sr-MnO films, which are of special interest for the design of new B-scalar magnetic field sensors used for magnetic field distribution measurements during railgun operation and other applications. [ABSTRACT FROM AUTHOR]

The magnetoresistance ( MR) of polycrystalline La0.83Sr0.17MnO3 thin films have been studied in high pulsed magnetic fields up to 38 T in the temperature range 100–300 K. The lucalox substrates were used to obtain polycrystalline structures with naturally formed grain boundaries (GBs) and crystallites whose dimensions were determined by film deposition temperature. It was found that the MR value is highest in the films having smallest crystallites. The main behaviour of high-field MR was analysed using modified Mott’s hopping model assuming that the GBs might be ferromagnetic with a Curie temperature TC being reduced in comparison with that of the crystallites interior. [ABSTRACT FROM AUTHOR]

The resistance relaxation after switch-off of high magnetic field pulses of 20-40 T was studied for two series of La0.67 Ca0.33 MnO3 thin films. The response dynamics was obtained for temperature range 77-300 K. It is shown that the relaxation time is sensitive to the temperature of the resistivity maximum and to magnetoresistive properties of a film. The observed relaxation times are assumed to be related to existence of magnetic domains or intergrain material. [ABSTRACT FROM AUTHOR]