About Me

Developing nonlinear soft X-ray spectroscopy to watch electrons, spins, and orbitals respond to light on femtosecond timescales.

I am a Ph.D. candidate in Iwao Matsuda Group at the Department of Chemistry, School of Science, The University of Tokyo. My research sits at the intersection of ultrafast light–matter interaction, nonlinear optics, and soft X-ray science at X-ray free-electron lasers.

Through experiments primarily conducted at SACLA BL1, I develop spectroscopic and imaging techniques that resolve element-specific dynamics of electronic, spin, orbital, and symmetry-related phenomena — in systems relevant to semiconductors, energy materials, and magnetic information storage. My goal is to uncover the microscopic physics of these light-driven processes, and to advance coherent, element-selective probes for the materials science of the next decade.

News

2026.03

Published “Rotational Anisotropy Soft X-ray Second-Harmonic Generation from GaAs” in e-Journal of Surface Science and Nanotechnology.

2026.03

Received the ISSP Best Poster Design Award at the Institute for Solid State Physics, The University of Tokyo.

Show earlier news

2025.11

Concluded my visiting scholarship at UC Berkeley, Zuerch Lab, Sep-Nov 2025.

2024.10

Awarded the SPRING-GX Fellowship for doctoral study at The University of Tokyo.

2024.10

Started my Ph.D. in Chemistry, School of Science, at The University of Tokyo.

Education

The University of Tokyo Tokyo, Japan

Ph.D. in Chemistry, School of Science

Oct. 2024 - Jul. 2027 (Expected)

The University of Tokyo Tokyo, Japan

Master of Science in Chemistry

Oct. 2022 - Sep. 2024

Xiamen University Xiamen, China

Bachelor of Science in Physics

Sep. 2018 - Jun. 2022

Research Experience

University of California, Berkeley California, USA

Visiting Student Scholar · Michael W. Zuerch Lab

Sep. 2025 - Nov. 2025

RIKEN / SACLA XFEL Hyogo, Japan

Research Assistant · SACLA beamline experiments

Apr. 2023 - Apr. 2024

Xiamen University Xiamen, China

Research Assistant · Lixiang Chen Lab

Jun. 2022 - Sep. 2022

Research

Soft X-ray Second-Harmonic Generation in GaAs

Developing rotational-anisotropy soft X-ray second-harmonic generation as an element-specific nonlinear probe of symmetry, bonding, and electronic structure in non-centrosymmetric semiconductors. This work aims to establish coherent soft X-ray spectroscopy as a tool for resolving buried structural and electronic responses that are difficult to access with conventional optical probes.

XFEL Nonlinear Optics Semiconductors

Ultrafast Electronic Dynamics in NiO

Using element-specific time-resolved soft X-ray absorption spectroscopy to probe photoinduced electronic dynamics in the strongly correlated material NiO. By tracking transient changes at core-level resonances, this project explores how charge, orbital, and lattice degrees of freedom reorganize after optical excitation, with relevance to ultrafast control of correlated and energy-related materials.

Ultrafast XAS Correlated Materials

Orbitronics in FeCo / CuO Heterostructures

Applying time-resolved soft X-ray SHG and XMCD to investigate element-specific ultrafast orbital angular momentum generation and transfer across magnetic / oxide interfaces. The broader goal is to clarify how light-driven orbital, spin, and interfacial currents can be harnessed for next-generation spintronic and orbitronic devices.

Orbitronics XMCD Heterostructures

Publications

* equal contribution · † corresponding author · See also Google Scholar.

  1. Seeing Trajectory Without Imaging by Exploring Both Radial Momentum and Orbital Angular Momentum of Light
    Xingyu Su, Xiaodong Qiu†, Jingyi Wang, Dongkai Zhang, Ling Hong, Fei Lin, Shiyao Fu†, Yuan Ren†, Lixiang Chen†
    Laser & Photonics Reviews·2026·First Author·Cover Feature
    Laser & Photonics Reviews cover featuring this article
  2. Rotational Anisotropy Soft X-ray Second-Harmonic Generation from GaAs
    Xingyu Su, Toshihide Sumi, Masafumi Horio†, Yuya Kubota, Shigeki Owada, Gota Yamaguchi, Yasuyuki Hirata, Yifu Liu, Yanze Guan, Tadashi Togashi, Kensuke Tono, Yoshihiro Miyauchi, Makina Yabashi, Iwao Matsuda
    e-Journal of Surface Science and Nanotechnology·2026·First Author
  3. Turbulence-Resilient Detection of the Rotational Doppler Effect with Cylindrical Vector Beams
    Jingyi Wang*, Xingyu Su*, Tong Liu, Ling Hong, Haoxu Guo, Xiaodong Qiu, Yuan Ren, Lixiang Chen†
    Optics Express·2023·Co-first Author

Talks & Presentations

Mar. 2026 · Xiamen, China

Xiamen University

Presentation: Probing Buried Interfaces: Time-Resolved Soft X-ray Nonlinear Spectroscopy at X-ray Free Electron Laser

Jan. 2026 · Sendai, Japan

The 39th Annual Meeting of the Japanese Society for Synchrotron Radiation Research

Oral Presentation: The Development of Soft X-ray Nonlinear Spectroscopy in SACLA BL1

Oct. 2025 · Berkeley, USA

University of California, Berkeley

Presentation: The Development of Soft X-ray Nonlinear Spectroscopy in SACLA BL1

Show earlier talks

Jul. 2025 · Boston, USA

Gordon Research Conference on X-ray Science

Oral Presentation: The Development of Soft X-ray Nonlinear Spectroscopy in SACLA BL1

Oct. 2024 · Kitakyushu, Japan

The 10th International Symposium on Surface Science

Poster: Development of Beam-Focusing Time-Resolved X-ray Nonlinear Optics Spectroscopy

Awards & Scholarships

ISSP Best Poster Design AwardMar. 2026
Institute for Solid State Physics, The University of Tokyo.
International Research Opportunities for Students ScholarshipApr. 2025
Support for visiting research at UC Berkeley.
SPRING-GX FellowshipOct. 2024
Graduate scholarship support for doctoral study in Japan.