Linearly implicit methods for Allen-Cahn equation

It is well known that the Allen-Cahn equation satisfies a nonlinear stability property, i.e., the free-energy functional decreases in time. Linearly implicit integrators have been de-veloped for energy-preserving methods for conservative systems with polynomial Hamil-tonians, which are based on the concept of polarization. In this paper, we construct lin-early implicit methods for gradient flows preserving the energy dissipation by polarizing the free-energy functional. Two-step linearly implicit methods are derived for the Allen -Cahn equation inheriting energy dissipation law. Numerical experiments for one-, two-, and three-dimensional Allen-Cahn equations demonstrate the energy dissipation and the accuracy of the linearly implicit methods.(c) 2023 Elsevier Inc. All rights reserved.