Experimental and simulation studies of the processing of nanoscale materials: Inert gas condensation and ion irradiation methods

Experimental and simulation studies of the processing of nanoscale materials by inert gas condensation and ion irradiation methods have been conducted.; In the first part of this work, Molecular Dynamics simulations of the inert gas condensation processes have been performed to investigate various kinetic aspects of vapor phase condensation as well as the structure of single-component and binary particles produced by condensation. A kinetic rate approach has been developed for description of the scaling of different condensation processes. Inclusion of a novel nucleation reaction from cluster splitting by vapor atoms was central to this model in order to account for the observed scaling dependencies.; In the second part of this thesis, phase separation behavior in thin CoxCu1-x films under irradiation at different temperatures has been systematically studied. Development of phase separation in irradiated films (estimates of the size of Co precipitates and concentration of Co in solution) was monitored with the use of magnetic measurements.; Analysis of magnetization data in the framework of superparamagnetic theory revealed that at irradiation temperatures Ti below T i ∼350°C, phase separation in Cu-Co films of all compositions stabilizes at high doses (by 5 x 1015 ions/cm 2), indicating the existence of temperature-dependent steady states for these alloys under irradiation. At temperatures higher than 350°C, macroscopic-like coarsening is observed. At low temperatures (room temperature and below), FC/ZFC (field cooled/zero field cooled) measurements clearly show the randomizing effect of irradiation. The observed phase separation behavior of Cu-Co system under irradiation fits well with the predictions of the theoretical model of Enrique and Bellon for immiscible alloy films under irradiation.