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Physical Sciences and Mathematics Commons

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Physics Faculty Research & Creative Works

2003

Mathematical models

Articles 1 - 2 of 2

Full-Text Articles in Physical Sciences and Mathematics

Disorder-Induced Rounding Of Certain Quantum Phase Transitions, Thomas Vojta Mar 2003

Disorder-Induced Rounding Of Certain Quantum Phase Transitions, Thomas Vojta

Physics Faculty Research & Creative Works

We study the influence of quenched disorder on quantum phase transitions in systems with overdamped dynamics. For Ising order-parameter symmetry disorder destroys the sharp phase transition by rounding because a static order parameter can develop on rare spatial regions. This leads to an exponential dependence of the order parameter on the coupling constant. At finite temperatures the static order on the rare regions is destroyed. This restores the phase transition and leads to a double exponential relation between critical temperature and coupling strength. We discuss the behavior based on Lifshitz-tail arguments and illustrate the results by simulations of a model …


Temperature Dependence Of Droplet Nucleation In A Yukawa Fluid, Jinsong Li, Gerald Wilemski Feb 2003

Temperature Dependence Of Droplet Nucleation In A Yukawa Fluid, Jinsong Li, Gerald Wilemski

Physics Faculty Research & Creative Works

We have studied the temperature dependence of gas-to-liquid nucleation in Yukawa fluids with gradient theory and density functional theory. Each of these nonclassical theories exhibits a weaker (i.e., better) temperature dependence than classical nucleation theory. At fixed temperature, the reversible work to form a critical nucleus found from gradient theory approaches the value given by density functional theory as the supersaturation increases. At high temperatures, the two theories remain quite close over a wide range of vapor densities. As the temperature is reduced, the difference between the two theories increases with decreasing vapor density. Compared to the classical theory we …