Exact macroscopic description of phase segregation in model alloys with long range interactions.
نویسندگان
چکیده
We derive an exact nonlinear nonlocal macroscopic equation for the time evolution of the conserved order parameter rsr, td of a microscopic model binary alloy undergoing phase segregation: a d-dimensional lattice gas evolving via Kawasaki exchange dynamics, satisfying detailed balance for a Hamiltonian with a long range pair potential gdJsgjxjd. The macroscopic evolution is on the spatial scale g21 and time scale g22, in the limit g ! 0. The domain coarsening, described by interface motion, is similar to that obtained from the Cahn-Hilliard equation.
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ورودعنوان ژورنال:
- Physical review letters
دوره 76 7 شماره
صفحات -
تاریخ انتشار 1996