Near-optimal perfectly matched layers for indefinite Helmholtz problems
Abstract
A new construction of an absorbing boundary condition for indefinite Helmholtz problems on unbounded domains is presented. This construction is based on a near-best uniform rational interpolant of the inverse square root function on the union of a negative and positive real interval, designed with the help of a classical result by Zolotarev. Using Krein's interpretation of a Stieltjes continued fraction, this interpolant can be converted into a three-term finite difference discretization of a perfectly matched layer (PML) which converges exponentially fast in the number of grid points. The convergence rate is asymptotically optimal for both propagative and evanescent wave modes. Several numerical experiments and illustrations are included.
Cite
@article{arxiv.1507.06265,
title = {Near-optimal perfectly matched layers for indefinite Helmholtz problems},
author = {Vladimir Druskin and Stefan Güttel and Leonid Knizhnerman},
journal= {arXiv preprint arXiv:1507.06265},
year = {2015}
}
Comments
Accepted for publication in SIAM Review. To appear 2016