Research

Our research focuses on understanding and controlling ultrafast phenomena in quantum materials using advanced optical and terahertz (THz) techniques. By probing the interactions among charge, spin, orbital, and lattice degrees of freedom on femtosecond to picosecond timescales, we seek to uncover new physical mechanisms and develop concepts for next-generation information and sensing technologies.

Ultrafast Spectroscopy of Quantum Materials

Many fundamental processes in solids occur on ultrafast timescales ranging from femtoseconds (10⁻¹⁵ s) to picoseconds (10⁻¹² s). Using femtosecond laser spectroscopy, we investigate how electronic, spin, and lattice excitations evolve far from equilibrium and how these dynamics determine material functionality.

Research Topics

• Optical pump–probe spectroscopy

• Optical pump–THz probe spectroscopy

• Carrier and exciton dynamics

• Nonequilibrium phase transitions

• Coherent collective excitations

• Ultrafast transport phenomena

Scientific Questions

• How do electrons, spins, and phonons interact immediately after photoexcitation?

• Can ultrafast optical excitation induce transient phases inaccessible under equilibrium conditions?

• What determines the relaxation pathways of nonequilibrium quantum materials?

THz Spin-Orbitronics

Spin-orbit coupling enables efficient conversion between charge, spin, and orbital angular momentum. We explore ultrafast spin transport and spin-charge interconversion processes using terahertz spectroscopy and spintronic THz emission techniques.

Research Topics

• Spin Hall and orbital Hall effects

• Spin-to-charge conversion

• Charge-to-spin conversion

• Spintronic THz emitters

• Ultrafast spin currents

• Low-symmetry and topological materials

Scientific Questions

• How are spin and orbital angular momentum generated and transported on ultrafast timescales?

• What material properties maximize spin-charge conversion efficiency?

• Can spintronic THz emitters provide new insights into nonequilibrium spin dynamics?

THz Magnonics

Magnons, the quanta of spin waves, offer a promising platform for low-power information processing. Our research aims to understand and manipulate magnon dynamics in the terahertz frequency regime, particularly in antiferromagnetic and quantum magnetic materials.

Research Topics

• THz magnon spectroscopy

• Antiferromagnetic spin dynamics

• Coherent magnon excitation

• Magnon transport

• Spin-wave manipulation

• Ultrafast magnetic switching

Scientific Questions

• How can magnons be generated and controlled at THz frequencies?

• What governs magnon transport in antiferromagnetic systems?

• Can magnonic excitations be harnessed for ultrafast information technologies?

Quantum Sensing

Quantum sensing exploits quantum coherence and light–matter interactions to achieve highly sensitive measurements of physical quantities. We develop optical and terahertz-based sensing approaches for probing quantum materials, magnetic phenomena, and emergent electronic states.

Research Topics

• THz sensing and imaging

• Magneto-optical sensing

• Quantum-enhanced measurement techniques

• Spin-based sensing platforms

• Spectroscopic characterization of quantum materials

Scientific Questions

• How can quantum coherence improve sensing sensitivity and precision?

• What new information can be extracted from terahertz and optical probes?

• Can quantum materials serve as active platforms for next-generation sensors?

Experimental Techniques

Our laboratory combines state-of-the-art ultrafast optical systems with terahertz spectroscopy and thin-film material platforms.

Core Capabilities

• Femtosecond laser spectroscopy

• Optical pump–probe measurements

• Optical pump–THz probe spectroscopy

• THz emission spectroscopy

• Time-resolved magneto-optical spectroscopy

• Spintronic THz generation and detection

• Thin-film and heterostructure characterization

• Data-driven analysis of ultrafast dynamics