Sanghyeon Yu (유상현)

I am an assistant professor in the department of mathematics at Korea University.

I went to ETH Zurich for my postdoctoral research under Prof. Habib Ammari. I got my Ph.D. in mathematics from KAIST under the supervision of Prof. Mikyoung Lim. I received my bachelor's degree in physics from Korea University.

Affiliation: Department of Mathematics, Korea University

Address: 618 Asan Science Building, 145 Anam-ro, Seongbuk-gu, Seoul 02841, South Korea

Phone: +82-2-3290-3078

Email: sanghyeon_yu (at) korea (dot) ac (dot) kr

CURRICULUM VITAE (Updated December 10 th, 2019) [Link]


RESEARCH INTEREST

  • Applied Mathematics, Partial Differential Equations (PDEs), Metamaterials, Wave Propagation, Inverse Problems, Invisibility Cloaking


SELECTED PUBLICATIONS ( * : corresponding author )

  1. S. Yu* and H. Ammari, Plasmonic interaction between nanospheres, SIAM Review (Research Spotlights section) 60 (2018), 356-385. [Link]

  2. S. Yu* and H. Ammari, Hybridization of Singular Plasmons via Transformation Optics, PNAS (Proceedings of the National Academy of Sciences) 116 (2019) 13785-13790 https://doi.org/10.1073/pnas.1902194116. [Link]

  3. H. Kang and S. Yu*, Quantitative characterization of stress concentration in the presence of closely spaced hard inclusions in two-dimensional linear elasticity, Archive for Rational Mechanics and Analysis 232 (2019), 121-196. [Link]

  4. H. Ammari*, E. O. Hiltunen and S. Yu, Subwavelength guided modes for acoustic waves in bubbly crystals with a line defect, Journal of the European Mathematical Society (JEMS), to appear. [Link]

  5. H. Ammari*, E. O. Hiltunen and S. Yu, A high-frequency homogenization approach near the Dirac points in bubbly honeycomb crystals, Archive for Rational Mechanics and Analysis, to appear. [Link]


FULL PUBLICATIONS LIST

Book

  1. H. Ammari, B. Fitzpatrick, H. Kang, M. Ruiz, S. Yu and H. Zhang, Mathematical and Computational Methods in Photonics and Phononics, Mathematical Surveys and Monographs, Volume 235 (2018), American Mathematical Society.


Papers (in press)

  1. H. Ammari, E. O. Hiltunen and S. Yu, A high-frequency homogenization approach near the Dirac points in bubbly honeycomb crystals, Archive for Rational Mechanics and Analysis, to appear. [Link]

  2. H. Ammari, B. Fitzpatrick, H. Lee, E. O. Hiltunen and S. Yu, Honeycomb-lattice Minnaert bubbles, SIAM Journal on Mathematical Analysis, to appear. [Link]

  3. H. Ammari, B. Davies and S. Yu, Close-to-touching acoustic subwavelength resonators: eigenfrequency separation and gradient blow-up, SIAM Multiscale Modeling and Simulation, to appear. [Link]

  4. H. Ammari, B. Davies, E.O. Hiltunen and S. Yu, Topologically protected edge modes in one-dimensional chains of subwavelength resonators, Journal de Mathématiques Pures et Appliquées, to appear. [Link]

  5. H. Ammari, E. O. Hiltunen and S. Yu, Subwavelength guided modes for acoustic waves in bubbly crystals with a line defect, Journal of the European Mathematical Society (JEMS), to appear. [Link]


Papers (published)

  1. H. Kang and S. Yu, A proof of the Flaherty-Keller formula on the effective property of densely packed elastic composites, Calculus of Variations and Partial Differential Equations 59 (2020), 22. [Link]

  2. S. Yu and H. Ammari, Hybridization of Singular Plasmons via Transformation Optics, PNAS (Proceedings of the National Academy of Sciences) 116 (2019) 13785-13790 https://doi.org/10.1073/pnas.1902194116. [Link]

  3. H. Kang and S. Yu, Quantitative characterization of stress concentration in the presence of closely spaced hard inclusions in two-dimensional linear elasticity, Archive for Rational Mechanics and Analysis 232 (2019), 121-196. [Link]

  4. H. Ammari, M. Putinar, M. Ruiz, S. Yu and H. Zhang, Shape reconstruction of nanoparticles from their associated plasmonic resonances, Journal de Mathématiques Pures et Appliquées 122 (2019), 23-48. [Link]

  5. H. Ammari, B. Fitzpatrick, H. Lee, S. Yu and H. Zhang, Double-negative acoustic metamaterials, Quaterly of Applied Mathematics. 77 (2019), 767-791. [Link]

  6. H. Ammari, B. Fitzpatrick, H. Lee, E. O. Hiltunen and S. Yu, Subwavelength resonances of encapsulated bubbles, Journal of Differential Equations 267 (2019), 4719-4744. [Link]

  7. H. Ammari, W. Wu and S. Yu, Double-negative electromagnetic metamaterials due to chirality, Quaterly of Applied Mathematics 77 (2019), 105-130. [Link]

  8. S. Yu and H. Ammari, Plasmonic interaction between nanospheres, SIAM Review (Research Spotlights section) 60 (2018), 356-385. [Link]

  9. H. Ammari, B. Fitzpatrick, E. O. Hiltunen and S. Yu, Subwavelength localized modes for acoustic waves in bubbly crystals with a defect, SIAM Journal on Applied Mathematics 78 (2018), 3316-3335. [Link]

  10. H. Ammari, D. Choi and S. Yu, A mathematical and numerical framework for near-field optics, Proceedings of the Royal Society A 474 (2018), 20180150. [Link]

  11. H. Ammari, M. Ruiz, S. Yu and H. Zhang, Reconstructing fine details of small objects by using plasmonic spectroscopic data. Part II: The strong interaction regime, SIAM Journal on Imaging Sciences 11 (2018), 1931–1953. [Link]

  12. H. Ammari, M. Ruiz, S. Yu and H. Zhang, Field expansions for systems of strongly coupled plasmonic nanoparticles, SIAM Journal on Numerical Analysis 56 (2018), 2029-2044. [Link]

  13. H. Ammari, M. Ruiz, S. Yu, and H. Zhang, Reconstructing fine details of small objects by using plasmonic spectroscopic data, SIAM Journal on Imaging Sciences 11 (2018), 1-23. [Link]

  14. K. Ando, Y. Ji, H. Kang, K. Kim and S. Yu, Spectral properties of the Neumann-Poincaré operator and cloaking by anomalous localized resonance for the elasto-static system, European Journal of Applied Mathematics 29 (2018), 189– 225. [Link]

  15. K. Ando, H. Kang, K. Kim and S. Yu, Spectrum of Neumann-Poincaré operator on annuli and cloaking by anomalous localized resonance for linear elasticity, SIAM Journal on Mathematical Analysis 49 (2017), 4232-4250. [Link]

  16. H. Ammari, B. Fitzpatrick, H. Lee, S. Yu and H. Zhang, Subwavelength phononic bandgap opening in bubbly media, Journal of Differential Equations 263, (2017) 5610–5629. [Link]

  17. H. Kang, M. Lim and S. Yu, Spectral resolution of the Neumann-Poincaré operator on intersecting disks and analysis of plasmon resonance, Archive for Rational Mechanics and Analysis 226 (2017), 83-115. [Link]

  18. S. Yu and M. Lim, Shielding at a distance due to anomalous resonance, New Journal of Physics 19 (2017), 033018. [Link]

  19. H. Ammari, M. Ruiz, W. Wu, S. Yu, and H. Zhang, Mathematical and numerical framework for metasurfaces using thin layers of periodically distributed plasmonic nanoparticles, Proceedings of the Royal Society A 472 (2016), 20160445. [Link]

  20. H. Ammari, M. Ruiz, S. Yu, and H. Zhang, Mathematical analysis of plasmonic resonances for nanoparticles: the full Maxwell equations, Journal of Differential Equations 261 (2016), 3615-3669. [Link]

  21. H. Kang, K. Kim, H. Lee, J. Shin and S. Yu, Spectral properties of the Neumann-Poincaré operator and uniformity of estimates for the conductivity equation with complex coefficients, Journal of London Mathematical Society (2) 93 (2016), 519-546. [Link]

  22. M. Lim and S. Yu, Asymptotics of the solution to the conductivity equation in the presence of adjacent circular inclusions with finite conductivities, Journal of Mathematical Analysis and Applications 421 (2015), 131-156. [Link]

  23. H. Ammari, J. Garnier, H. Kang, M. Lim and S. Yu, Generalized polarization tensors for shape description, Numerische Mathematik 126 (2014), 199-224. [Link]

  24. H. Ammari, H. Kang, H. Lee, M. Lim and S. Yu, Enhancement of near cloaking for the full Maxwell equations, SIAM Journal on Applied Mathematics 73 (2013), 2055-2076. [Link]

  25. H. Ammari, P. Garapon, F. Jouve, H. Kang, M. Lim, and S. Yu, A new optimal control approach for the reconstruction of extended inclusions, SIAM Journal on Control and Optimization 51 (2013), 1372-1394. [Link]

  26. M. Lim and S. Yu, Reconstruction of the shape of an inclusion from Elastic Moment Tensors, Contemporary Mathematics 548, 2011.


Preprints

  1. H. Ammari, B. Davies, H. Lee, E. O. hiltunen and S. Yu, High-order exceptional points and enhanced sensing in subwavelength resonator arrays. arXiv:008.00799. [Link]

  2. H. Ammari, H. Kang, D. W. Kim and S. Yu, Quantitative estimates for stress concentration of the Stokes flow between adjacent circular cylinders, arXiv:2003.06578. [Link]

  3. H. Ammari, B. Davies, H. Lee, E. O. Hiltunen and S. Yu, Exceptional points in parity-time-symmetric subwavelength metamaterials, arXiv:2003.07796. [Link]

  4. M. Lim and S. Yu, Stress concentration for two nearly touching circular holes, arXiv:1705.10400. [Link]

  5. M. Lim and S. Yu, Asymptotic analysis for superfocusing of the electric field in between two nearly touching metallic spheres, arXiv:1412.2464. [Link]