I am a theoretical physicist working in the field of condensed matter physics, recognized for pioneering contributions to orbitronics. My research focuses on understanding the quantum mechanical properties of angular momentum in nonequilibrium, including its generation, transport, relaxation, and interactions with other physical quantities, such as current-induced orbital accumulation and current, conversion between orbital and spin currents, and angular momentum transfer between electron’s spin and orbital angular momenta, lattice orders, and magnetic textures.

I theoretically showed robustness of the orbital Hall effect [PRL 121, 086602 (2018)], the effect predicted in mid 2000’s but was not widely accepted for its fragility in crystals. Following my prediction that the orbital Hall effect is gigantic in light metals such as Ti, it was experimentally confirmed in [Nature 619, 52 (2023)]. Additionally, I proposed the concept of orbital torque—magnetization dynamics driven by nonequilibrium processes [PRR 2, 013177 (2020); PRR 2, 033401 (2020); PRL 130, 246701 (2023)]—which has since been validated through multiple experiments [PRL 125, 177201 (2020); NatComm 12, 6710 (2021); NatPhys 20, 1896 (2024), etc.]. Recently, my colleagues and I demonstrated terahertz radiation arising from ultrafast dynamics [NatNano 18, 1132 (2023)] and introduced the concept of ‘orbital pumping’ [NatElec 7, 646 (2024)], the reciprocal effect to orbital torque.

Nowadays, orbitronics has emerged as a pivotal research area in condensed matter physics due to its crucial implications for quantum transport, correlated phenomena, and geometric and topological effects. They manifest in versatile material platforms, including two-dimensional materials, topological matter, unconventional magnets, oxides, multiferroics, and superconductors. Nonequilibrium orbital angular momentum and its associated currents, once thought unattainable in solids, now offer novel tools for probing and controlling hidden complex orders, their dynamics, and the transport of their elementary excitations.

The physical principles underlying the generation, detection, and manipulation of nonequilibrium orbital angular momentum and related variables hold promise for developing next-generation devices. Orbitronic technologies could address limitations of conventional electronics, offering advantages in operation speed, manufacturing costs, environmental impact, and energy efficiency.

In my research, I place great importance on bridging theoretical physics with real materials and experimental observations. This involves developing general theoretical frameworks, performing first-principles calculations for real materials, and collaborating closely with experimentalists. While my expertise is centered around condensed matter theory and first-principles calculations, my ultimate goal is to uncover fundamental principles and apply them to device technologies. I am deeply interested in exploring novel materials and innovative experimental techniques. Please feel free to reach out to discuss potential collaborations!