Single-sided acoustic beam splitting based on parity-time symmetry

Tuo Liu, Guancong Ma, Shanjun Liang, He Gao, Zhongming Gu, Shuowei An, Jie Zhu

Research output: Journal article publicationJournal articleAcademic researchpeer-review

1 Citation (Scopus)

Abstract

Unidirectional reflectionless resonance observed in parity-time-symmetric systems suggests a promising strategy to produce extremely asymmetric scattering. Inspired by such a unique feature, we propose a single-sided acoustic beam splitter that splits sound incident from a specific side but is totally transparent for sound incident from the opposite side. The unidirectional response is due to a parity-time-symmetric refractive index distribution. At the exceptional point when the real-part index and gain/loss modulations are balanced, it interacts with obliquely incident waves in a single-sided manner. In addition, by engineering the sidewall boundaries within an acoustic waveguide, we provide a general approach for obtaining the required complex refractive index, in which we show that the resistive or reactive component of the sidewall impedance can independently modulate the gain/loss or the real-part index. Based on this, a planar waveguide implementation of the single-sided acoustic beam splitter is demonstrated. Our study presents opportunities enabled by exploiting parity-time-symmetric systems in a higher-dimensional space and could find applications such as sensing and communication in a wide range of wave systems including but not limited to acoustics.

Original languageEnglish
Article number014306
JournalPhysical Review B
Volume102
Issue number1
DOIs
Publication statusPublished - 1 Jul 2020

ASJC Scopus subject areas

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics

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