Research Groups

▶ Our group aims to introduce multidisciplinary viewpoints on wave mechanics and its applications to intelligent systems.

- Wave mechanics cover a variety of fields in physics, from classical to quantum phenomena. Despite the different specific properties of each field, there exists the mathematical similarity in various wave mechanics, including photonics, quantum mechanics, acoustics, elastic waves, and electronic circuits.

- This underlying similarity inspires the multidisciplinary connection between different waves, as demonstrated in the research of quantum-optical analogy, acoustic topology, non-Hermitian electronic circuits, and the quantum analogy of elastic waves. Furthermore, this multidisciplinary viewpoint can be more generalized to network theory, biomimetics, and machine learning.

- Based on this multidisciplinary perspective, we try to (i) devise new design strategies for wave systems, (ii) reveal novel wave phenomena, and (iii) achieve superior device performance. The research goal of our laboratory is the realization of "intelligent wave systems," ultimately focusing on the construction of wave-based artificial intelligence: ultra-fast inference, ultra-low power consumption, and reasonable feature sizes.

In detail, we are now focusing on achieving the neuromorphic realization of intelligent photonic systems: "Thinking with Light."

▶ Photonic AI
- Scale-Free photonic neural networks
- Photonic neurons/synapses
- Photonic activation functions

▶ AI Wave Mechanics
- Convolutional Neural Networks (CNNs) for wave-matter interactions
- Graph Neural Networks (GNNs) for wave-matter interactions
- Scale invariance in neural networks and engineered materials

▶ Disordered Photonics
- Engineered disorder in photonics
- Crystal-like spectra/scattering in disordered materials
- Scale-free materials with hub dynamics

▶ Open-System/Non-Euclidean/Topological Photonics
- Chirality, oscillation quenching, and topology in open systems
- Hyperbolic lattices and their topology & deformations
- Flat-band photonics

[15] S. Yu* & N. Park*. Heavy tails and pruning in programmable photonic circuits for universal unitaries.
Nature Communications 14, 1853 (2023)

[14] J. Kim, D. Lee, S. Yu* & N. Park*. Unidirectional scattering with spatial homogeneity using correlated photonic time disorder.
Nature Physics 19, 726 (2023)

[13] S. Yu. Evolving scattering networks for engineering disorder.
Nature Computational Science 3, 128-138 (2023)
: Highlighted in News & Views, Nat. Comput. Sci.
: Cover Paper

[12] S. Choi, J. Kim, J. Kwak, N. Park* & S. Yu*. Topologically Protected All-Optical Memory.
Advanced Electronic Materials 8, 2200579 (2022): Cover Paper

[11] J. Kim, S. Park, S. Yu* & N. Park*. Machine-Engineered Active Disorder for Digital Photonics.
Advanced Optical Materials 10, 2102642 (2022): Cover Paper

[10] S. Yu†, C.-W. Qiu†, Y. Chong, S. Torquato* & N. Park*. Engineered Disorder in Photonics.
Nature Reviews Materials 6, 226 (2021): Invited Review Article

[09] S. Yu, X. Piao & N. Park. Machine learning identifies scale-free properties in disordered materials.
Nature Communications 11, 4842 (2020)

[08] S. Yu*, X. Piao & N. Park*. Topological Hyperbolic Lattices.
Physical Review Letters 125, 053901 (2020): Cover Paper

[07] S. Yu, X. Piao & N. Park. Neuromorphic Functions of Light in Parity‐Time‐Symmetric Systems.
Advanced Science 6, 1900771 (2019): Cover Paper

[06] S. Yu, X. Piao & N. Park. Bohmian Photonics for Independent Control of Phase and Amplitude of Waves.
Physical Review Letters 120, 193902 (2018)

[05] S. Yu, X. Piao, J. Hong & N. Park. Metadisorder for designer light in random systems.
Science Advances 2, e1501851 (2016)

[04] S. Yu†, H. S. Park†, X. Piao, B. Min & N. Park. Low-dimensional optical chirality in complex potentials.
Optica 3, 1025 (2016). Cover Paper

[03] S. Yu, X. Piao, J. Hong & N. Park. Interdimensional optical isospectrality inspired by graph networks.
Optica 3, 836 (2016)

[02] S. Yu, X. Piao, J. Hong & N. Park. Bloch-like waves in random-walk potentials based on supersymmetry.
Nature Communications 6, 8269 (2015)

[01] K. Chung†, S. Yu†, C. Heo, J. W. Shim, S. Yang, M. G. Han, H. Lee, Y. Jin, S. Y. Lee, N. Park & J. H. Shin. Flexible, Angle-Independent Structural Color Reflectors Inspired by Morpho Butterfly Wings.
Advanced Materials 24, 2375 (2012): Cover Paper, Highlighted in Nature