The Advanced Photon Source
a U.S. Department of Energy Office of Science User Facility

Yongseong “Yong” Choi

Contact Information
Argonne National Laboratory
9700 S. Cass Ave
431/E004
Argonne, Il 60439

Phone: 252-2271 | Fax: 252-7392

E-Mail: ychoi@aps.anl.gov

Education/Experience
  • 2010 – present: Assistant Physicist, X-ray Science Division, Argonne National Laboratory
  • 2008 – 2010: Research Beamline Scientist, GeoSoilEnviroCARS, University of Chicago at Advanced Photon Source of Argonne National Laboratory
  • 2008-2008: Postdoctoral research associate, GeoSoilEnviroCARS, University of Chicago and Geology Department, Northern Illinois University
  • 2005-2007: Postdoctoral research associate, Materials Science Division, Argonne National Laboratory and Physics Department, University of Texas at Arlington
  • Northwestern University, Evanston, Illinois: Ph. D in Materials Science and Engineering, 2005
  • Rutgers University, New Brunswick, New Jersey: BS in Mechanical Engineering, 1999
Research Interests
  • Interfacial effects in magnetic films (Exchange-spring permanent magnets, transition metal oxide films)
  • Depth-/element-resolved structural/magnetic characterization using x-ray resonant magnetic scattering (x-ray magnetic reflectivity) and x-ray magnetic circular dichroism
  • Depth- and element-resolved characterization using combination of x-ray scattering and spectroscopy techniques (long period x-ray standing wave)
Selected Publications
  1. "Quantifying interlayer exchange coupling via layer-resolved hysteresis loops in antiferromagnetically coupled manganite/nickelate superlattices", J. Park, D. R. Lee, Y. Choi, J. W. Freeland, K. B. Lee, S. K. Sinha, D. R. Nikolaev, and A. M. Goldman, Appl. Phys. Lett. 95, 102504 (2009).
  2. "Enhancement of induced V polarization due to rough interfaces in polycrystalline V/Fe/V trilayers", C. Clavero, J. R. Skuza, Y. Choi, D. Haskel, C. Sánchez-Hanke, R. Loloee, M. Zhernenkov, M. R. Fitzsimmons, and R. A. Lukaszew, Phys. Rev. B 80, 024418 (2009).
  3. "Application of grazing incidence x-ray fluorescence technique to discriminate and quantify implanted solar wind", K. Kitts, Y. Choi, P. J. Eng, S. K. Ghose, S. R. Sutton, and B. Rout, J. Appl. Phys. 105, 064905 (2009).
  4. "Competing interactions and complex magnetism at SrRuO3/SrMnO3 interfaces", Y. Choi, Y. C. Tseng, D. Haskel, D. E. Brown, D. Danaher, and O. Chmaissem, Appl. Phys. Lett. 93, 192509 (2008).
  5. "X-ray resonant magnetic scattering study of magnetization reversals in a nanoscale spin-valve array", D. R. Lee, J. W. Freeland, Y. Choi, G. Srajer, V. Metlushko, and B. Ilic, Phys. Rev. B 76, 144425 (2007).
  6. "Controlled Interface Profile in Sm-Co/Fe Exchange-Spring Magnets" , Y. Choi, J. S. Jiang, J. E. Pearson, S. D. Bader, J. Kavich, J. W. Freeland and J. P. Liu, Appl. Phys. Lett. 91, 072509 (2007).
  7. "Origin of Recoil Loops in Sm-Co/Fe Exchange-Spring Magnets", Y. Choi, J. S. Jiang, J. E. Pearson, S. D. Bader, and J. P. Liu, Appl. Phys. Lett. 91, 022502 (2007).
  8. "Ferromagnetic Mn moments at SrRuO3/SrMnO3 interfaces", Y. Choi, Y. Z. Yoo, O. Chmaissem, A. Ullah, S. Kolesnik, C. W. Kimball, D. Haskel, J. S. Jiang, and S. D. Bader, Appl. Phys. Lett. 91, 022503 (2007).
  9. "Role of Diffused Co Atoms in Improving Effective Exchange Coupling in Sm-Co/Fe Spring Magnets", Y. Choi, J. S. Jiang, Y. Ding, R. A. Rosenberg, J. E. Pearson, S. D. Bader, A. Zambano, M. Murakami, I. Takeuchi, Z. L. Wang, and J. P. Liu, Phys. Rev. B 75, 104432 (2007).
  10. "Layer-resolved study of magnetic interaction effects in heterostructure dot arrays", Y. Choi, D.R. Lee, J.W. Freeland, G. Srajer, and V. Metlushko, Appl. Phys. Lett. 88, 112502 (2006).
  11. "Twisted magnetization states near the compensation temperature of Fe/Gd multilayers: Anisotropy and surface-termination effects", Y. Choi, D. Haskel, A. Cady, J.C. Lang, D.R. Lee, G. Srajer, S.J. Jiang, and S.D. Bader, Phys. Rev. B 73, 174401 (2006).
  12. "Temperature evolution of the Gd magnetization profile in strongly coupled Gd/Fe multilayers" , Y. Choi, D. Haskel, R.E. Camley , D.R. Lee, J.C. Lang, G. Srajer, S.J. Jiang, and S.D. Bader, Phys. Rev. B 70, 134420 (2004).
  13. "Measurement of local magnetization in the buried layer of a pseudo-spin-valve submicron wire", Y. Choi, D. Haskel, D.R. Lee, J.C. Lang, G. Srajer, J.S. Im, J. Appl. Phys. 95, 7028 (2004).