Standard Correlation Length Research Articles

Variation of electronic density in the superconducting phase transition in Nb3Al

The variation of electronic density in the superconducting phase transition in the classical superconductor Nb3Al with critical temperature Tc=18.6 K was studied using 73Ge emission Mossbauer spectroscopy. A comparison of the results obtained and the data available for the 67Zn isotope in the lattices of high-temperature superconductors revealed a correlation between the electronic density variation at the Mossbauer probe nuclei sites and the value of Tc. This correlation is assumed to be related to the dependence of the electronic density variation on the standard correlation length.

Correlation between Local and Long-Range Structure in Compressible Supercritical Lennard-Jones Fluids: State-Point Dependence

Evaluation of local-density-specific radial distribution functions in a two-dimensional supercritical Lennard-Jones fluid has enabled us to elucidate how the correlations between a solvent particle's local density and the extended surrounding solvent structure change as a function of the thermodynamic condition. We find that the standard correlation length provides only a very crude measure of these correlations and that, for example, such inhomogeneity-induced correlations remain present at bulk densities surprisingly far from the critical density in this two-dimensional system. Additionally, these local-density-specific radial distribution functions provide insight into the state-point dependence of the origin of mean local-density enhancements, showing that the potential-induced and the correlation-induced contributions both die out rapidly with increasing temperature, whereas they are maximally important at different bulk densities.