On the radius of spatial analyticity for the quintic fourth-order nonlinear Schrödinger equation on ℝ2

In this paper, we prove that the uniform radius of spatial analyticity [Formula: see text] of the solution at time [Formula: see text] to the two-dimensional quintic fourth-order nonlinear Schrödinger equation [Formula: see text] is bounded from below by [Formula: see text] as [Formula: see text], given the initial data that is analytic with fixed radius [Formula: see text]. The proof of our main theorems is based on a method of almost conservation law in the modified Gevrey spaces, space–time estimates and Sobolev embedding.