Mechanics–Physics Convergence 

Translating concepts from topology, symmetry, resonance, and interference into controllable mechanical phenomena.

What do we do? 

At MOA Lab, we use mechanical structures as experimental and computational platforms for exploring advanced concepts in wave physics. Our research connects structural mechanics with ideas originating from condensed-matter physics, acoustics, photonics, and classical wave theory.

We investigate topological edge states, bound states and bound bands in the continuum, flat and quasi-flat bands, symmetry-protected modes, defect-induced scattering, and interference-driven resonances. We are particularly interested in how global wave behavior emerges from the interaction between structural symmetry, internal vibration modes, and coupling to the surrounding continuum.

Mechanical systems provide a unique setting for these studies. Their geometry, boundary conditions, interactions, and nonlinearities can be directly designed, modified, and measured. This allows abstract physical concepts to be observed as tangible structural motion.

Our work also follows the reverse direction: fundamental wave physics provides new principles for engineering mechanical systems. Topology can stabilize localized modes, symmetry can suppress radiation, and interference can produce sharply selective transmission, reflection, or energy confinement.

Why does it matter?

Advanced wave phenomena reveal ways of controlling energy that are not available through conventional structural design.

Topological modes can provide robust localization in the presence of imperfections. Bound states in the continuum can confine energy despite overlapping with propagating waves. Interference-driven resonances can create narrow transmission or reflection features with high spectral selectivity. These principles can support compact mechanical resonators, high-sensitivity sensors, energy-harvesting systems, vibration filters, waveguides, and structures with highly localized or protected dynamic responses.

More broadly, this research creates a bridge between fundamental physics and mechanical engineering, allowing discoveries in wave science to inspire new structural functions.

Representative Publications

1. Y. Jang, S. Kim, D. Lee, E. Kim, and J. Rho, “Bound states to bands in the continuum in cylindrical granular crystals,” Physical Review Letters 134, 136901 (2025).

2. Y. Jang*, S. Kim*, E. Kim, and J. Rho, “Singular topological edge states in locally resonant metamaterials,” Science Bulletin 70, 1080–1086 (2025).

3. Y. Jang, S. Kim, M. Kim, G. Kim, E. Kim, and J. Rho, “Mode-coupled infinite topological edge state in bulk-lattice-merged mechanical Su–Schrieffer–Heeger chain,” Extreme Mechanics Letters 77, 102334 (2025).

4. Y. Jang, E. Kim, and J. Rho, “Scattering of waves in locally resonant woodpile structures with impurities,” Physical Review E (2026).