Sanghyeon Yu 

Postdoctoral Researcher
Seminar für Angewandte Mathematik
Department of Mathematics
ETH Zurich

Phone: +41 44 632 6965
Email: sanghyeon.yu (at) sam (dot) math (dot) ethz (dot) ch
Address:  HG J 48, Rämistrasse 101, 8092 Zurich, Switzerland




I am a postdoctoral researcher at ETH Zurich.
My postdoc advisor is Prof. Habib Ammari. I received my Ph.D. from KAIST under the supervision of Prof. Mikyoung Lim.



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

PUBLICATIONS

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.  [Link]
Papers
  1. H. Ammari, B. Fitzpatrick, H. Lee, E. O. Hiltunen and S. Yu, Honeycomb-lattice Minnaert bubbles, arXiv:1811.03905.  [Link]
  2. H. Ammari, B. Fitzpatrick, H. Lee, E. O. Hiltunen and S. Yu, Subwavelength resonances of encapsulated bubbles, arXiv:1810.12756.  [Link]
  3. S. Yu and H. Ammari, Hybridization of Singular Plasmons via Transformation Optics, arXiv:1807.09255.  [Link]
  4. H. Ammari, B. Fitzpatrick, H. Lee, S. Yu and H. Zhang, Double-negative acoustic metamaterials, arXiv:1709.08177.  [Link]
  5. H. Kang and S. Yu, A proof of the Flaherty-Keller formula on the effective property of densely packed elastic composites, arXiv:1707.02205.  [Link]
  6. M. Lim and S. Yu, Stress concentration for two nearly touching circular holes, arXiv:1705.10400.  [Link]
  7. M. Lim and S. Yu, Asymptotic analysis for superfocusing of the electric field in between two nearly touching metallic spheres, arXiv:1412.2464.  [Link]
  8. H. Ammari, B. Fitzpatrick, E. O. Hiltunen and S. Yu, Subwavelength localized modes for acoustic waves in bubbly crystals with a defect, to appear in SIAM Journal on Applied Mathematics.  [Link]
  9. H. Kang and S. Yu, Quantitative characterization of stress concentration in the presence of closely spaced hard inclusions in two-dimensional linear elasticity, to appear in Archive for Rational Mechanics and Analysis (2018). DOI : https://doi.org/10.1007/s00205-018-1318-1 [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), no. 3, 1931–1953.  [Link]
  12. H. Ammari, M. Ruiz, S. Yu and H. Zhang, Field expansions for systems of strongly coupled plasmonic nanoparticles, to appear in SIAM Journal on Numerical Analysis.  [Link]
  13. S. Yu and H. Ammari, Plasmonic interaction between nanospheres, SIAM Review (Research Spotlights section) 60 (2018), 356-385.  [Link]
  14. 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]
  15. H. Ammari, M. Putinar, M. Ruiz, S. Yu and H. Zhang, Shape reconstruction of nanoparticles from their associated plasmonic resonances, to appear in Journal de Mathématiques Pures et Appliquées (doi.org/10.1016/j.matpur.2017.09.003).  [Link]
  16. H. Ammari, W. Wu and S. Yu, Double-negative electromagnetic metamaterials due to chirality, to appear in Quaterly of Applied Mathematics.  [Link]
  17. 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]
  18. 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]
  19. 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]
  20. 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]
  21. S. Yu and M. Lim, Shielding at a distance due to anomalous resonance, New Journal of Physics 19 (2017), 033018.  [Link]
  22. 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]
  23. 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]
  24. 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]
  25. 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]
  26. H. Ammari, J. Garnier, H. Kang, M. Lim and S. Yu, Generalized polarization tensors for shape description, Numerische Mathematik 126 (2014), 199-224.  [Link
  27. 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]
  28. 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]
  29. M. Lim and S. Yu, Reconstruction of the shape of an inclusion from Elastic Moment Tensors, Contemporary Mathematics 548, 2011.

EDUCATION
  • Ph.D. in Mathematical Sciences, Aug. 2015
    KAIST, Daejeon, Republic of Korea
    - Advisor: Prof. Mikyoung Lim
  • M.S. in Mathematical Sciences, Feb. 2011
    KAIST, Daejeon, Republic of Korea
    Advisor: Prof. Mikyoung Lim
  • B.S. in Physics, Feb. 2009
    Korea Univesity, Republic of Korea

HONOR AND AWARDS
  • National Junior Research Fellowship (2012 - 2015)
    - National Research Foundation of Korea
  • Lotte Foundation Scholarship (2007)
    - Lotte Foundation
  • Outstanding TA Award (Calculus I, 2012 Spring)
    - Department of Mathematical Sciences, KAIST

VISITING EXPERIENCES
  • Ecole Normale Supérieure, Paris, France (Oct. 8 - Oct. 21, 2012)
    Département de mathématiques et applications

  • Columbia University, New York, United States (Sep. 1, 2013 - Jan. 31, 2014)
    Department of Applied Physics and Applied Mathematics

  • Hong Kong University of Science and Technology (HKUST), Hong Kong (Jan. 09 - Jan. 23, 2017)
    Department of Mathematics

  • Radon Institute for Computational and Applied Mathematics (RICAM), Linz, Austria (Mar. 14 - Mar. 17, 2017)

TEACHING  EXPERIENCES

     Teaching Assistant, Department of Mathematical Sciences, KAIST
  • Numerical Analysis II, 2018 Spring (Recitation, Grading)
  • Mathematical and Computational Methods in Photonics, 2015 Autumn - 2017 Autumn  (Recitation)
  • Numerical Analysis II, 2017 Spring (Recitation, Grading)

     Teaching Assistant, Department of Mathematical Sciences, KAIST
  • Calculus I, 2012 Spring (Recitation, Grading)
  • Differential Equations and Applications, 2011 Spring (Recitation, Grading)
  • Analysis II, 2011 Fall (Recitation, Grading)
  • Analysis II, 2009 Fall (Recitation)