Nonconforming finite element method is studied for a linearized backward fully-discrete scheme of the Ginzburg-Landau equation with the quadrilateral EQ rot 1 element. The unconditional convergent result of order O(h + ) in the broken H 1 -norm is deduced rigorously based on a splitting technique, by which the ratio between the subdivision parameter h and the time step is removed. Furthermore, numerical results are provided to confirm the theoretical analysis. The analysis developed herein can be regarded as a framework to deal with the unconditional convergent analysis of the Ginzburg-Landau equation for other known low order nonconforming elements.
KEYWORDS
EQ rot1 element, Galerkin method, Ginzburg-Landau equation, quadrilateral EQ rot 1 element, linearized scheme, quadrilateral meshes, unconditional convergent estimates
INTRODUCTIONThe Ginzburg-Landau equation is an important nonlinear evolution equation, which can be used to describe a vast of phenomena from nonlinear waves to second-order phase transitions, from superconductivity, superfluidity and Bose-Einstein condensation to liquid crystal and strings in field theory [1]. The existence and uniqueness of weak solution, the regularity and long-time behavior of the solution for the problem can be found in [2][3][4][5]. Numerical methods for Ginzburg-Landau equation include spectral method [6][7][8], finite difference method [9,10], and finite element method (FEM) [11,12] have already been studied. In this article, we are concerned with the following complex Ginzburg-Landau equationu(X, t) = 0, (X, t) ∈ Ω × [0, T], u(X, 0) = u 0 (X), X ∈ Ω,(1.1) Numer Methods Partial Differential Eq. 2020;36:329-341. wileyonlinelibrary.com/journal/num