Related Experiment Video
Updated: Mar 10, 2026

Studying Cavitation Enhanced Therapy
Published on: April 9, 2021
Observation of an exceptional point in a two-dimensional ultrasonic cavity of concentric circular shells
Younghoon Shin1, Hojeong Kwak1,2, Songky Moon1
1School of Physics and Astronomy, Institute of Applied Physics, Seoul National University, Seoul 151-742, Korea.
Abstract:
We report observation of an exceptional point in circular shell ultrasonic cavities in both theory and experiment. In our theoretical analysis we first observe two interacting mode groups, fluid- and solid-based modes, in the acoustic cavities and then show the existence of an EP of these mode groups exhibiting a branch-point topological structure of eigenfrequencies around the EP. We then confirm the mode patterns as well as eigenfrequency structure around the EP in experiments employing the schlieren method, thereby demonstrating utility of ultrasound cavities as experimental platform for investigating non-Hermitian physics.
More Related Videos
07:44Characterization of Full Set Material Constants and Their Temperature Dependence for Piezoelectric Materials Using Resonant Ultrasound Spectroscopy
Published on: April 27, 2016
08:19Induction of Microstreaming by Nonspherical Bubble Oscillations in an Acoustic Levitation System
Published on: May 9, 2021
Related Concept Videos
Standing Waves in a Cavity
Sound Waves: Resonance
Thin-Walled Hollow Shafts
Shock Waves
When the source's speed approaches the speed of sound, constructive interference between successive wavefronts emitted by the source occurs immediately behind it. Initially, scientists believed that this constructive interference would result in such high...
Sound as Pressure Waves
The pressure fluctuation depends on the difference in displacements between the successive points in the...
Gauss's Law: Cylindrical Symmetry