Dr. Justin (Junseok) Ma

Justin (Junseok) Ma, Ph.D.

junseok.ma@kaist.ac.kr
Jang Young-Sil Postdoctoral Research Fellow
Nature Sciences Research Institute (자연과학연구소) & Soft Material Assembly Group (SMA Group)
Korea Advanced Institute of Science and Technology (KAIST)
LinkedIn · ResearchGate · GitHub · Google Scholar · CV (PDF)

Research Interests

Education

Professional Experience

Publications (20+)

Dissertations

  1. J. Ma, “A Study of Liquid Crystal-based Phase Shifter in the Millimeter-wave Range for Utilizing Current Mass-production Technology of Display Industry,” M.S. Thesis, Dept. of Electrical Engineering, POSTECH, Korea, 2021.
  2. J. Ma, “Development of Multifunctional Reconfigurable Liquid Crystal Devices Using Drop-on-Demand Printing,” Ph.D. Dissertation, Dept. of Electrical Engineering, POSTECH, Korea, 2025.

Journal Publications

  1. J. Ma*, Dang-Oh Kim, Hee Seong Yun, and Dong-Ki Yoon* “Decoupling Optical Ringing from True Permittivity Dynamics in Twisted–Nematic Liquid Crystals for 160-GHz RIS Applications”, Appl. Phys. Lett., 2026. (Drafting)
  2. Jinge Guo†, Xuke Qiu†, Runchen Zhang, Qihao Han, Jiahe Cui, An Wang, Zimo Zhao, Yifei Ma, Mengmeng Li, Waqas Kamal, J. Ma , Yongge Ma, Steve J Elston, Alfonso A. Castrejón-Pita, Stephen M Morris, and Chao He,, “Adaptive complex beam manipulation via inkjet-printed negative anisotropy liquid crystal droplets”, Adv. Func. Mater., 2026. (Drafting)
  3. J. Ma* et al., “Twisted-Nematic Configuration Enables Fast, Ringing-Free, and Continuous Phase Response: A Thickness-Dependent Critical Damping Framework”, Adv. Func. Mater., 2026. (Drafting)
  4. D. Kim+*, J. Ma+*, et al., “Ultrafast, Critically Damped Liquid-Crystal Phase Shifters Enable 360° Analog Beam Steering in 160 GHz Reconfigurable Intelligent Surfaces”, Light. Sci. Appl., 2026. (Drafting)
  5. J. Ma+*, D. Lee+, et al., “Electrically Programmable Inkjet-Printed Liquid Crystal Pixels for Ultra-Low-Power, Thermally Stable Full-Color and Transmittance Control”, Adv. Mater., 2025. (Submitted)
  6. A. Pradeep, Y. Montelongo, J.S. Ma, Z. Xu, T. Wang, J. Qin, C. Nourshagh, S. J. Elston, and S. M. Morris, “From Millimeters to Microns: A Hybrid Strategy for Reconfigurable Liquid-Crystal Patterning”, Small Methods., 2025 (Submitted).
  7. B. Mee et al., “Reconfigurable Optically-Transparent Antenna Using Drop-on-Demand Printed Nematic Liquid Crystals”, Adv. Eng. Mater., 2025 (Submitted).
  8. I.-B. Kong, T.-H. Seo, J. Ma, S.-O. Cha, W.-S. Kim, and S.-W. Lee, “Isolated High-Voltage-Gain Full-Range Soft-Switching DC/DC Converter Using Built-in Transformer and Coupled Inductors with Minimum Design Constraints”, IEEE Trans. Ind. Electron., 2026 (Accepted).
  9. J.Y. Choi, J.S. Ma, W.S. Kim*, “Tunable High-Selectivity Wideband Bandpass Filter Using Triple-Mode Stub-Loaded Resonators Based on Liquid Crystals”, IEEE Access, 2025. (Link)
  10. J. Ma, W. Kamal, A. Pradeep, A. J. Orr, S.-W. Oh, J.-Y. Choi, J. Guo, B. Mee, H.-W. Oh, J.-H. Lee, A. A. Castrejon-Pita*, S. J. Elston*, W.-S. Kim*, and S. M. Morris*, “Advanced image-integrated smart windows using printed electrochromic polymer-dispersed liquid crystal droplets,” Adv. Opt. Mater., 2025. (Featured as HOT TOPIC: Liquid Crystals) (Link)
  11. J. Ma, A. Pradeep, S.W. Oh, J.H. Lee, J.Y. Choi, S.O. Cha, H.W. Oh, W.S. Kim*, “Operating temperature control in push-pull azobenzene-doped liquid crystal light-driven devices via a UV absorber”, Dyes and Pigments, 2025. (Link)
  12. S.-H. Lee+, S.-G. Park+, J. Ma, W.-S. Kim, and S.-W. Oh*, “High-performance switchable visor for augmented reality using low-voltage, fast-response cholesteric liquid crystals,” Dyes and Pigments, 2025. (Link)
  13. S.-O. Cha, J.-H. Ka, I.-B. Kong, J. Ma, S.-Y. Park, and W.-S. Kim*, “Off-Center Rotational Dynamics in Virtual Reality: Effects on Cybersickness and Presence,” IEEE Access, 2025. (Link)
  14. A. Pradeep*, U. Mur, J. Ma, N. Spiller, Y. Jin, W. Kamal, S. J. Elston*, and S. M. Morris*, “Locking metastable topological domains in nematic liquid crystal Pi cells,” Adv. Funct. Mater., 2025. (Featured as Editor’s Choice) (Link)
  15. J.-Y. Choi, J. Ma, and W.-S. Kim*, “Reconfigurable wideband bandpass filter using stepped impedance resonator based on liquid crystals,” Electronics, 2025. (Link)
  16. S. Park, J. Ma, S. Oh, and W. Kim, “Blur image representation in defocus using generalized Gaussian kernel,” Inf. Disp., 2025. (Link)
  17. J.-Y. Choi, J. Ma, H. Oh, and W.-S. Kim*, “Reconfigurable narrow-band bandpass filter using electrically-coupled open-loop resonators based on liquid crystals,” J. Phys. D: Appl. Phys., 2024. (Link)
  18. J.-H. Lee, J. Ma, C.-H. An, G.-H. Lee, and S.-W. Oh*, “Advanced light: Liquid crystals-based ultra-broadband polarization rotator for functional smart devices,” Small Methods, 2023. (Link)
  19. J. Ma, J.-Y. Choi, S. Park, I. Kong, D. Kim, C. Lee, Y. Youn, M. Hwang, S.-W. Oh*, W. Hong*, and W.-S. Kim*, “Liquid crystals for advanced smart devices with microwave and millimeter-wave applications: Recent progress for next-generation communication,” Adv. Mater., 2023. (Selected as Frontispiece Cover) (Link)
  20. H. Shin+, J. Ma+, J.-Y. Choi+, and W.-S. Kim*, “Phase shifting enhancement of a substrate-integrated waveguide phase shifter based on liquid crystal,” Appl. Sci., 2023. (+ equal contribution) (Link)
  21. J. Ma, J.-Y. Choi, H. Shin, J. Lee, S.-W. Oh*, and W.-S. Kim*, “An evaluation of surface-active agent hexadecyltrimethylammonium bromide with vertical self-alignment properties to align liquid crystals for various cell gap conditions,” Appl. Sci., 2022. (Link)
  22. J. Ma, J.-Y. Choi, S.-W. Oh, and W.-S. Kim, “Liquid-crystal-based floating-electrode-free coplanar waveguide phase shifter with an additional liquid-crystal layer for 28-GHz applications,” J. Phys. D: Appl. Phys., 2021. (Link)
  23. J. Ma, J.-Y. Choi, and W.-S. Kim, “액정의 고주파 대역 특성과 RF 응용 기술 동향,” Information Display, 22(3), 2021. (Link)

International Conference Presentations

  1. H. Oh, S. Park, J.-Y. Choi, J. Ma, S. Choi, and W.-S. Kim, “Analysis of Meander Delay Line Liquid Crystal Phase Shifter using Director Angle Extraction,” IMID, 2024.
  2. J.-Y. Choi, J. Ma, H. Oh, and W.-S. Kim, “Characterization of Nematic Liquid Crystals at 10 GHz using an Open Stub Resonator,” AP-S/URSI, 2024. (Link)
  3. J.-Y. Choi, J. Ma, H. Shin, and W.-S. Kim, “Reconfigurable Phased Array Antenna Based on Liquid Crystal with Miniaturized Bandpass Filter,” ISAP, Oct. 31–Nov. 3, 2022. (Link)
  4. H. Shin, J.-Y. Choi, J. Ma, and W.-S. Kim, “Phase Shift Enhancement of Substrate Integrated Waveguide Phase Shifter Using Liquid Crystal,” IMID, Korea, Aug. 23–26, 2022. (Link)
  5. J. Ma, J.-Y. Choi, H. Shin, and W.-S. Kim, “Comparative Analysis of Liquid-Crystal Driving between the Grounded-Coplanar Waveguide and the Floating-Electrode-Free Coplanar Waveguide in Liquid-Crystal Phase Shifters,” AP-S/URSI, 2022. (Link)
  6. J. Ma, H. Shin, and W.-S. Kim, “Analysis about Novel Design of Liquid Crystal Based Floating Electrode Free Coplanar Waveguide Phase Shifter for Performance Improvement,” IMID, Korea, Aug. 25–27, 2021.
  7. S. Cha, J. Ma, and W.-S. Kim, “Concept and Numerical Modeling for Virtual Acceleration Sense on Vestibular Organ using Focused Ultrasound,” IMID, Korea, Aug. 25–28, 2020.

Domestic Conference Presentations

  1. J. Ma, S.-W. Oh, J.-Y. Choi, H. Oh, S. M. Morris*, and W.-S. Kim*, “Enhancing Light-driven Polymer Stabilized Liquid Crystal Smart Devices,” BLCS, 2024. (BLCS)
  2. J.-Y. Choi, J. Ma, H. Oh, and W.-S. Kim*, “Characterization of Nematic Liquid Crystal at 10 GHz using Director Angle Extraction,” Korea Liquid Crystal Conference, 2024.
  3. J.-Y. Choi, J. Ma, S. Park, and W.-S. Kim*, “전기적 커플링 오픈 스터브를 이용한 소형 액정 기반 가변 광대역 대역저지 필터,” IEIE Summer Conference, 2023.

Academic Service — Journal Reviewer

Scholarships, Honors & Awards