Designing Orbitronic Materials by Chirality, Topology, and Geometry
일시 : 2026-05-06 16:00 ~
연사 : 고동욱 (고려대학교 물리학과)
담당 : Prof. Sunghoon Jung, Prof. Joonho Jang, Prof. Yongjoo Baek
장소 : 56동105호
Orbitronics explores how the orbital motion of electrons, which has been long overlooked compared to their charge and spin, can serve as a new carrier of information in quantum materials [1]. In recent years, both theory and experiment have established the existence of orbital currents and their potential for controlling magnetism, opening new possibilities for next-generation electronic devices such as magnetic memory [2–4]. Despite this progress, several key challenges remain: how to reliably generate and detect orbital currents, how to make them robust against material imperfections, and how to enhance their efficiency to a practical level.
In this talk, I will present a unifying perspective on these challenges based on three guiding principles: chirality, topology, and quantum geometry. First, I will show how chiral crystal structures naturally give rise to orbital-momentum locking, providing a route to generate orbital currents [5]. Next, I will discuss how certain chiral materials host topological electronic states—what we term orbital chiral fermions—which can stabilize orbital transport [6]. Finally, I will highlight the role of the quantum geometry of electronic wave functions in amplifying orbital responses, offering a pathway toward stronger and more robust effects [7]. I will conclude with an outlook on how these ideas may shape the future of orbitronics and its role in energy-efficient information technologies.
[1] DG et al. Europhys. Lett. 135, 37001 (2021).
[2] DG et al. Phys. Rev. Lett. 121, 086602 (2018).
[3] Y.-G. Choi, D. Go et al. Nature 619, 52 (2023).
[4] D. Jo, DG et al. npj Spintronics 2, 19 (2024).
[5] DG et al. In preparation.
[6] Hagiwara, DG et al. Adv. Mater. 2418040 (2025).
[7] H. Lee, DG et al. arXiv:2603.19875.