title: Inverse design of high-Q wave filters in two-dimensional phononic crystals by topology optimization.
abstract: Topology optimization of a waveguide-cavity structure in phononic crystals for designing narrow band filters under the given operating frequencies is presented in this paper. We show that it is possible to obtain an ultra-high-Q filter by only optimizing the cavity topology without introducing any other coupling medium. The optimized cavity with highly symmetric resonance can be utilized as the multi-channel filter, raising filter and T-splitter. In addition, most optimized high-Q filters have the Fano resonances near the resonant frequencies. Furthermore, our filter optimization based on the waveguide and cavity, and our simple illustration of a computational approach to wave control in phononic crystals can be extended and applied to design other acoustic devices or even opto-mechanical devices.
authors.affiliation: Institute of Engineering Mechanics, Beijing Jiaotong University, Beijing 100044, China; Department of Civil Engineering, University of Siegen, D-57068 Siegen, Germany.
authors.forename: Hao-Wen
authors.initials: HW
authors.lastname: Dong
authors.affiliation: Institute of Engineering Mechanics, Beijing Jiaotong University, Beijing 100044, China. Electronic address: yswang@bjtu.edu.cn.
authors.forename: Yue-Sheng
authors.initials: YS
authors.lastname: Wang
authors.affiliation: Department of Civil Engineering, University of Siegen, D-57068 Siegen, Germany. Electronic address: c.zhang@uni-siegen.de.
authors.forename: Chuanzeng
authors.initials: C
authors.lastname: Zhang
keywords: Fano resonances; Filters; Phononic crystals; Q factor; Symmetric resonance; Topology optimization