A survey of the possible autocatalytic crystallization processes called explosive crystallization in liquid and solid states is given. The explosive liquid-phase epitaxy with laterally moving coupled interfaces of melting and crystallization in amorphous silicon layers on insulators is investigated by the use of an experimental equipment consisting of three synchronized lasers supplying the temperature pulses for ignition, spreading, and stopping of the explosive front. The velocity of this explosive crystallization front measured by use of time-resolved reflectivity of a test beam is compared with the results of model calculations. The results are in good agreement. The crystal structure was investigated by optical and transmission electron micrography and represents crystalline laminae grown preferentially in the 〈110〉 direction over a distance of about 100 μm. Areas of some millimeters in diameter can be crystallized by this method.

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We have investigated the superconducting (T c ,J c ,H c2 ), electron transport, structural ͓x-ray diffraction ͑XRD͒, Rutherford backscattering spectrometry ͑RBS͔͒, and surface ͓x-ray photoelectron spectroscopy ͑XPS͒, ultraviolet photoelectron spectroscopy ͑UPS͔͒ properties of BaNbO 3Ϫx and Ba 2 Nb 5 O x epitaxial and oriented thin films grown on different substrates (Al 2 O 3 , NdGaO 3 , SrTiO 3 , and YSZ͒. Superconducting films with T c ϭ14 K and unusually high H c2 (0)ϭ28 T have been prepared on Al 2 O 3 substrates. At the same time, films on NdGaO 3 exhibit behavior similar to granular superconductors, while strong pure metal electron transport behavior of the films on SrTiO 3 was observed. XPS and RBS investigations show that the composition of these films is almost the same, while UPS study evidenced the Fermi edge position corresponding to semimetallic behavior of the films for all substrates.