Keun Hyuk Ahn
Keun Hyuk Ahn
(K. Ahn, K. H. Ahn, Ken Ahn, Keun Hyuk Ahn) Associate Professor, Physics
480 Tiernan Hall (TIER)
Education
Ph.D.; Johns Hopkins University; Physics; 2000
M.S.; Seoul National University, South Korea; Physics; 1994
B.S.; Seoul National University, South Korea; ; 1992
M.S.; Seoul National University, South Korea; Physics; 1994
B.S.; Seoul National University, South Korea; ; 1992
Website
2025 Spring Courses
MTSE 690 - DIRECTED STUDY IN MTSE
MTSE 725 - INDEPENDENT STUDY I
MTSE 790A - DOCTORAL DISSERTATION
PHYS 791 - DOCTORAL SEMINAR
MTSE 700B - MASTER'S PROJECT
MTSE 726 - INDEPENDENT STUDY II
PHYS 701B - MASTER'S THESIS
PHYS 725 - INDEPENDENT STUDY I
MTSE 593 - GRADUATE CO-OP WORK EXP IV
MTSE 701B - MASTER'S THESIS
PHYS 700B - MASTER'S PROJECT
MTSE 792B - PRE-DOCTORAL RESEARCH
PHYS 790A - DOCT DISSERTATION & RES
PHYS 701C - MASTER'S THESIS
PHYS 792 - PRE-DOCTORAL RESEARCH
MTSE 725 - INDEPENDENT STUDY I
MTSE 790A - DOCTORAL DISSERTATION
PHYS 791 - DOCTORAL SEMINAR
MTSE 700B - MASTER'S PROJECT
MTSE 726 - INDEPENDENT STUDY II
PHYS 701B - MASTER'S THESIS
PHYS 725 - INDEPENDENT STUDY I
MTSE 593 - GRADUATE CO-OP WORK EXP IV
MTSE 701B - MASTER'S THESIS
PHYS 700B - MASTER'S PROJECT
MTSE 792B - PRE-DOCTORAL RESEARCH
PHYS 790A - DOCT DISSERTATION & RES
PHYS 701C - MASTER'S THESIS
PHYS 792 - PRE-DOCTORAL RESEARCH
Teaching Interests
Introductory Physics courses (Phys 102), Graduate level Solis State Physics (Phys 661)
Past Courses
PHYS 102: GENERAL PHYSICS
PHYS 102: GENERAL PHYSICS I
PHYS 105: PHYSICS A
PHYS 335: INTRO THERMODYNAMICS
PHYS 433: ELECTROMAGNETISM II
PHYS 661: SOLID-STATE PHYSICS
PHYS 791: DOCTORAL SEMINAR
PHYS 102: GENERAL PHYSICS I
PHYS 105: PHYSICS A
PHYS 335: INTRO THERMODYNAMICS
PHYS 433: ELECTROMAGNETISM II
PHYS 661: SOLID-STATE PHYSICS
PHYS 791: DOCTORAL SEMINAR
Research Interests
Theoretical and Computational Condensed Matter Physics
Journal Article
Kai Qian, David Apigo, Karmela Padavic, Keun Hyuk Ahn, Smitha Vishveshwara, Camelia Prodan. 2023. “Observation of Majorana-like bound states in metamaterial-based Kitaev chain analogs.” Physical Review Research - Letter/American Physical Society, vol. 5, pp. L012012.
Kai Qian, Linghua Zhu, Keun Hyuk Ahn, Camelia Prodan. 2020. “Observation of flat frequency bands at open edges and antiphase boundary seams in topological mechanical metamaterials .” Phys Rev Lett, vol. 125, pp. 225501.
Linghua Zhu, Emil Prodan, Keun Hyuk Ahn. 2019. “Flat energy bands within antiphase and twin boundaries and at open edges in topological materials.” PHYSICAL REVIEW B-Rapid Communications/American Physical Society, vol. 99, pp. 041117(R).
Linghua Zhu, Tsezar Seman, Michel van Veenendaal, Keun Hyuk Ahn. 2018. “ Photoinduced Nonequilibrium Dynamics in Charge Ordered Materials.” Journal of Applied Physics, vol. 123, pp. 115112.
T. Wu, H. Chen, P. Gao, T. Yu, Z. Chen, Z. Liu, Keun Hyuk Ahn, X. Wang, S.-W. Cheong, Trevor A. Tyson. 2016. “Pressure dependent structural changes and predicted electrical polarization in perovskite RMnO3.” J. Phys.: Condens. Matter , vol. 28, pp. 056005.
Kai Qian, Linghua Zhu, Keun Hyuk Ahn, Camelia Prodan. 2020. “Observation of flat frequency bands at open edges and antiphase boundary seams in topological mechanical metamaterials .” Phys Rev Lett, vol. 125, pp. 225501.
Linghua Zhu, Emil Prodan, Keun Hyuk Ahn. 2019. “Flat energy bands within antiphase and twin boundaries and at open edges in topological materials.” PHYSICAL REVIEW B-Rapid Communications/American Physical Society, vol. 99, pp. 041117(R).
Linghua Zhu, Tsezar Seman, Michel van Veenendaal, Keun Hyuk Ahn. 2018. “ Photoinduced Nonequilibrium Dynamics in Charge Ordered Materials.” Journal of Applied Physics, vol. 123, pp. 115112.
T. Wu, H. Chen, P. Gao, T. Yu, Z. Chen, Z. Liu, Keun Hyuk Ahn, X. Wang, S.-W. Cheong, Trevor A. Tyson. 2016. “Pressure dependent structural changes and predicted electrical polarization in perovskite RMnO3.” J. Phys.: Condens. Matter , vol. 28, pp. 056005.
SHOW MORE
T. Yu, Trevor A. Tyson, H. Y. Chen, A. M. M. Abeykoon, Y. S. Chen, Keun Hyuk Ahn. 2014. “Absence of significant structural changes near the magnetic ordering temperature in small-ion rare earth perovskite RMnO3.” J. Phys. Condens. Matter , vol. 26, no. 49, pp. 495402.
Tsezar F Seman, Xuerong Liu, John P. Hill, Michel van Veenendaal, Keun Hyuk Ahn. 2014. “Momentum dependence in K-edge resonant inelastic x-ray scattering and its application to screening dynamics in CE-phase La0.5Sr1.5MnO4.” PHYSICAL REVIEW B/American Physical Society, vol. 90, pp. 045111.
Keun Hyuk Ahn, Tsezar F Seman, Turab Lookman, Alan R. Bishop. 2013. “Role of complex energy landscapes and strains in multiscale inhomogeneities in perovskite manganites.” PHYSICAL REVIEW B/American Physical Society, vol. 88, pp. 144415.
Xuerong Liu, Tsezar F Seman, Keun Hyuk Ahn, Michel van Veenendaal, D. Casa, D. Prabhakaran, A. T. Boothroyd, Hong Ding, John P. Hill. 2013. “Strongly momentum-dependent screening dynamics in La0.5Sr1.5MnO4 observed with resonant inelastic x-ray scattering.” PHYSICAL REVIEW B -Rapid/American Physical Society, vol. 87, pp. 201103 (R).
Tsezar F Seman, Jichan Moon, Keun Hyuk Ahn. 2012. “Symmetry-mode-based atomic-scale formalism of lattice dynamics.” Emergent Materials Research, vol. 2, pp. 5-16.
Tsezar F Seman, Keun Hyuk Ahn, Turab Lookman, Avadh Saxena, Alan R. Bishop, Peter B. Littlewood. 2012. “Effects of rare earth ion size on the stability of the coherent Jahn-Teller distortions in undoped perovskite manganites.” PHYSICAL REVIEW B/American Physical Society, vol. 86, pp. 184106.
Andrei Sirenko, Keun Hyuk Ahn. 2012. “Far-infrared spectra of the magnetic exchange resonances and optical phonons and their connection to magnetic and dielectric properties of Dy3Fe5O12 garnet.” Phys. Rev. B , vol. 86, no. 14, pp. 144112.
Trevor A. Tyson, T Wu, H Y Chen, J Bai, Keun Hyuk Ahn, K I Pandya, S B Kim, S-W. Cheong. 2011. “Measurements and ab initio molecular dynamics simulations of the high temperature ferroelectric transition in hexagonal RMnO3.” JOURNAL OF APPLIED PHYSICS/American Institute of Physics, vol. 110, pp. 084116.
P Gao, Z Chen, Trevor A. Tyson, T Wu, Keun Hyuk Ahn, Z Liu, R Tappero, S B Kim, S.-W. Cheong. 2011. “High-pressure structural stability of multiferroic hexagonal RMnO3 (R = Y, Ho, Lu).” PHYSICAL REVIEW B/American Physical Society, vol. 83, pp. 224113.
P D Rogers, Y J Choi, E C Standard, T D Kang, Keun Hyuk Ahn, A Dubroka, P Marsik, Ch Wang, C Bernhard, S Park, S.-W. Cheong, M Kotelyanskii, Andrei Sirenko. 2011. “Adjusted oscillator strength matching for hybrid magnetic and electric excitations.” PHYSICAL REVIEW B /American Physical Society, vol. 83, pp. 174407.
T. D. Kang, E. Standard, Keun Hyuk Ahn, Andrei Sirenko, G. L. Carr, S. Park, Y. J. Choi, M. Ramazanoglu, V. Kiryukhin, S.-W. Cheong. 2010. “Coupling between magnon and ligand-field excitations in magnetoelectric Tb3Fe5O12 garnet.” Physical Review B/ American Physical Society, vol. 82, pp. 014414.
Wenda Cao, N. Gorceix, R. Coulter, Keun Hyuk Ahn, T. R. Rimmele, Philip R. Goode. 2010. “Scientific instrumentation for the 1.6 m new solar telescope in big bear.” Astronomische Nachrichten, vol. 331, no. 6, pp. 636-639.
Z. Chen, Trevor A. Tyson, Keun Hyuk Ahn, Z. Zhong, J. Hu. 2010. “Origin of the non-linear pressure effects in perovskite manganites: Buckling of Mn–O–Mn bonds and Jahn–Teller distortion of the MnO6 octahedra induced by pressure.” Journal of Magnetism and Magnetic Materials/ Elsevier, vol. 322, pp. 3049.
Trevor A. Tyson, T. Wu, Keun Hyuk Ahn, S. B. Kim, S.-W. Cheong. 2010. “Local spin-coupled distortions in multiferroic hexagonal HoMnO3.” Physical Review B/ American Physical Society, vol. 81, pp. 054101.
Tsezar F Seman, Xuerong Liu, John P. Hill, Michel van Veenendaal, Keun Hyuk Ahn. 2014. “Momentum dependence in K-edge resonant inelastic x-ray scattering and its application to screening dynamics in CE-phase La0.5Sr1.5MnO4.” PHYSICAL REVIEW B/American Physical Society, vol. 90, pp. 045111.
Keun Hyuk Ahn, Tsezar F Seman, Turab Lookman, Alan R. Bishop. 2013. “Role of complex energy landscapes and strains in multiscale inhomogeneities in perovskite manganites.” PHYSICAL REVIEW B/American Physical Society, vol. 88, pp. 144415.
Xuerong Liu, Tsezar F Seman, Keun Hyuk Ahn, Michel van Veenendaal, D. Casa, D. Prabhakaran, A. T. Boothroyd, Hong Ding, John P. Hill. 2013. “Strongly momentum-dependent screening dynamics in La0.5Sr1.5MnO4 observed with resonant inelastic x-ray scattering.” PHYSICAL REVIEW B -Rapid/American Physical Society, vol. 87, pp. 201103 (R).
Tsezar F Seman, Jichan Moon, Keun Hyuk Ahn. 2012. “Symmetry-mode-based atomic-scale formalism of lattice dynamics.” Emergent Materials Research, vol. 2, pp. 5-16.
Tsezar F Seman, Keun Hyuk Ahn, Turab Lookman, Avadh Saxena, Alan R. Bishop, Peter B. Littlewood. 2012. “Effects of rare earth ion size on the stability of the coherent Jahn-Teller distortions in undoped perovskite manganites.” PHYSICAL REVIEW B/American Physical Society, vol. 86, pp. 184106.
Andrei Sirenko, Keun Hyuk Ahn. 2012. “Far-infrared spectra of the magnetic exchange resonances and optical phonons and their connection to magnetic and dielectric properties of Dy3Fe5O12 garnet.” Phys. Rev. B , vol. 86, no. 14, pp. 144112.
Trevor A. Tyson, T Wu, H Y Chen, J Bai, Keun Hyuk Ahn, K I Pandya, S B Kim, S-W. Cheong. 2011. “Measurements and ab initio molecular dynamics simulations of the high temperature ferroelectric transition in hexagonal RMnO3.” JOURNAL OF APPLIED PHYSICS/American Institute of Physics, vol. 110, pp. 084116.
P Gao, Z Chen, Trevor A. Tyson, T Wu, Keun Hyuk Ahn, Z Liu, R Tappero, S B Kim, S.-W. Cheong. 2011. “High-pressure structural stability of multiferroic hexagonal RMnO3 (R = Y, Ho, Lu).” PHYSICAL REVIEW B/American Physical Society, vol. 83, pp. 224113.
P D Rogers, Y J Choi, E C Standard, T D Kang, Keun Hyuk Ahn, A Dubroka, P Marsik, Ch Wang, C Bernhard, S Park, S.-W. Cheong, M Kotelyanskii, Andrei Sirenko. 2011. “Adjusted oscillator strength matching for hybrid magnetic and electric excitations.” PHYSICAL REVIEW B /American Physical Society, vol. 83, pp. 174407.
T. D. Kang, E. Standard, Keun Hyuk Ahn, Andrei Sirenko, G. L. Carr, S. Park, Y. J. Choi, M. Ramazanoglu, V. Kiryukhin, S.-W. Cheong. 2010. “Coupling between magnon and ligand-field excitations in magnetoelectric Tb3Fe5O12 garnet.” Physical Review B/ American Physical Society, vol. 82, pp. 014414.
Wenda Cao, N. Gorceix, R. Coulter, Keun Hyuk Ahn, T. R. Rimmele, Philip R. Goode. 2010. “Scientific instrumentation for the 1.6 m new solar telescope in big bear.” Astronomische Nachrichten, vol. 331, no. 6, pp. 636-639.
Z. Chen, Trevor A. Tyson, Keun Hyuk Ahn, Z. Zhong, J. Hu. 2010. “Origin of the non-linear pressure effects in perovskite manganites: Buckling of Mn–O–Mn bonds and Jahn–Teller distortion of the MnO6 octahedra induced by pressure.” Journal of Magnetism and Magnetic Materials/ Elsevier, vol. 322, pp. 3049.
Trevor A. Tyson, T. Wu, Keun Hyuk Ahn, S. B. Kim, S.-W. Cheong. 2010. “Local spin-coupled distortions in multiferroic hexagonal HoMnO3.” Physical Review B/ American Physical Society, vol. 81, pp. 054101.
COLLAPSE
Conference Abstract
“Flat Frequency Bands and Majorana-like Bound States in Topological Mechanical Metamaterials”
July (3rd Quarter/Summer) 2023.
“Observation of Phase Controllable Majorana-like Bound States in Metamaterial-based Kitaev Chain Analogues”
Bulletin of the American Physical Society, March 2022.
July (3rd Quarter/Summer) 2023.
“Observation of Phase Controllable Majorana-like Bound States in Metamaterial-based Kitaev Chain Analogues”
Bulletin of the American Physical Society, March 2022.
Conference Proceeding
“(INVITED TALK, about 4,000 attendees for conference) Role of Complex Energy Landscapes and Strains in Multiscale Inhomogeneities in Perovskite Manganites ”
TMS 2015 Annual Meeting Supplemental Proceedings , March 2015.
“Control and operation of the 1.6 m New Solar Telescope in Big Bear”
August 2014.
“Reverse resistance switching in polycrystalline Nb2O5 films ”
Thin Solid Films/ Elsevier, August 2010.
TMS 2015 Annual Meeting Supplemental Proceedings , March 2015.
“Control and operation of the 1.6 m New Solar Telescope in Big Bear”
August 2014.
“Reverse resistance switching in polycrystalline Nb2O5 films ”
Thin Solid Films/ Elsevier, August 2010.
Book
A. Anđić, J. Chae, H. Park, H. Yang, Keun Hyuk Ahn, Wenda Cao, Y. D. Park. 2015. “Connection between chromospheric events and photospheric dynamics.” 55-71 pp. ISBN 9783319121239.
Magazine/Trade Publication
“Self-Assembled Nano-Checkerboard Thin Films Studied by Reciprocal Space Mapping at CHESS”
CHESS News Magazine 2009, December 2009.
CHESS News Magazine 2009, December 2009.