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In recent years many groups have used Fisher, Fisher and Huse (FFH) dynamical scaling to investigate and demonstrate details of the superconducting phase transition. Some attention has been focused on two dimensions where the phase transition is of the Kosterlitz-Thouless-Berezinskii (KTB) type. Pierson et al. used FFH dynamical scaling almost exclusively to suggest that the dynamics of the two-dimensional superconducting phase transition may be other than KTB-like. In this work we investigate the ability of scaling behavior by itself to yield useful information on the nature of the transition. We simulate current-voltage (IV) curves for two-dimensional Josephson junction arrays with and without finite-size-induced resistive tails. We find that, for the finite-size effect data, the values of the scaling parameters, specifically the transition temperature and the dynamical scaling exponent z, depend critically on the magnitude of the contribution that the resistive tails make to the IV curves. In effect, the values of the scaling parameters depend on the noise floor of the measuring system.

We find that the ⁵⁵Mn NMR linewidth and Knight shift of icosahedral Ti₆₃Mn₃₇ (i-TiMn) are identical to those of the crystalline phases obtained upon annealing. Comparison of the linewidth in i-TiMn and a bcc Ti-Mn solid solution shows that the Mn sites in both phases have a nearly cubic or higher symmetry. These measurements and our analysis provide strong evidence for a large density of structurally ordered, highly symmetric sites in an icosahedral alloy and demonstrate that a high degree of structural disorder is not an intrinsic property of the icosahedral phase.

Isothermal measurements of the crystallization kinetics of icosahedral Al₈₆Mn₁₄ were made by differential scanning calorimetry and electrical resistivity in the temperature range 593–723 K. Transmission electron microscopy investigations of as-quenched samples showed that the icosahedral phase (i phase) occurs as dendritic nodules separated by α-Al. On crystallization, Al₆Mn nucleates at the i-phase boundary and grows into the i phase, while consuming the α-Al. An effective-medium theory is used to relate resistance changes to the volume fraction transformed. A Johnson-Mehl-Avrami analysis for the kinetics of transformation indicates continuous nucleation with diffusion-limited growth. Nonisothermal differential scanning calorimetry measurements were made and analyzed using a numerical model that assumes simultaneous nucleation and growth. Crude estimates are given for the diffusion coefficient for growth of the crystal phase in the i phase and a lower bound for the i-phase Al₆Mn interfacial energy.