Swift heavy ion-based materials science research at NSC

Effects of large electronic excitation in different types of materials, viz . metals, semiconductors, superconductors, polymers and organic crystals ar e being investigated using the swift heavy ions (SHI) of energies from 10 t o 270 MeV available from 15 UD NSC Pelletron. Defect production in semicond uctors, structural strain on electronic transport properties of materials h aving colossal magneto resistance (CMR), flux pinning in high T-c supercond uctors (HTS), desorption of hydrogen from polymers, ion beam mixing in meta l/Si interface and optical waveguide formation are some of our research act ivities. Resistivity and 1/f noise measurements from room temperature down to 77 K are used for the studies of SHI-induced defects into the materials. Quadrupole mass spectrometer (QMS) in the materials science beam line is u sed for the studies of radiolysis of polymers induced by SHI. For polymers, ion track diameters have been estimated by on-line monitoring of the loss of hydrogen (using ERD and QMS) during ion irradiation. An ultra high vacuu m scanning tunneling microscope (UHV STM) is being installed at the materia ls science beam line to study the individual damage created by SHI on the s olid surfaces. A three-axes goniometer has been installed for RBS-channelin g studies of various materials. Experimental facilities and the research wo rk carried out at Nuclear Science Centre are briefed. (C) 1999 Elsevier Sci ence B.V. All rights reserved.