Subwavelength resonances of encapsulated bubbles

JOURNAL OF DIFFERENTIAL EQUATIONS

卷:267

Article

Ammari, Habib¹  Fitzpatrick, Brian¹  Hiltunen, Erik Orvehed¹  Lee, Hyundae²  Yu, Sanghyeon¹ 

[1] Swiss Fed Inst Technol, Dept Math, Ramistr 101, CH-8092 Zurich, Switzerland

[2] Inha Univ, Dept Math, 253 Yonghyun Dong, Incheon 402751, South Korea

关键词: Bubble;    Subwavelength resonance;    Encapsulated bubble;    Thin coating;   

DOI  :  10.1016/j.jde.2019.05.013

来源: Elsevier

【 摘 要 】

The aim of this paper is to derive an original formula for the subwavelength resonance frequency of an encapsulated bubble with arbitrary shape in two dimensions. Using Gohberg-Sigal theory, we derive an asymptotic formula for this resonance frequency, as a perturbation away from the resonance of the uncoated bubble, in terms of the thickness of the coating. The formula is numerically verified in the case of circular bubbles, where the resonance can be efficiently computed using the multipole method. The approach involves the use of a pole-pencil decomposition of the leading order term in the asymptotic expansion of some integral operator in terms of the thickness of the coating, followed by the application of the generalized argument principle to find the characteristic value. This approach is quite general and can be applied to other subwavelength resonators such as coated plasmonic nanoparticles. (C) 2019 Elsevier Inc. All rights reserved.

【 授权许可】

Free