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arXiv · 2306.16939

High-accuracy Casimir-Polder force calculations using the Discontinuous Galerkin Time-Domain method

Philip Trøst Kristensen·Bettina Beverungen·Francesco Intravaia·Kurt Busch
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Abstract

We describe a numerical time-domain approach for high-accuracy calculations of Casimir-Polder forces near micro-structured materials. The use of a time-domain formulation enables the investigation of a broad range of materials described by advanced material models, including nonlocal response functions. We validate the method by a number of example calculations for which we thoroughly investigate the convergence properties of the method, and comparing to analytical reference calculations, we find average relative errors as low as a few parts in a million. As an application example, we investigate the anisotropy-induced repulsive behavior of the Casimir-Polder force near a sharp gold wedge described by a hydrodynamic Drude model.

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Philip Trøst Kristensen, Bettina Beverungen, Francesco Intravaia, Kurt Busch. 2023-06-29. High-accuracy Casimir-Polder force calculations using the Discontinuous Galerkin Time-Domain method. https://doi.org/10.1103/physrevb.108.205424

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