Key Advances
• Ultrafast-light-driven magnetic heterostructures exhibit concurrent demagnetization and emission of THz radiation.
• Despite being a primary experimental probe of spin-charge coupled dynamics and transport, there have been virtually no calculations of THz radiation from such systems since the inception of this field in 1996.
• We solved this longstanding problem by introducing two new complementary frameworks, which combine time-dependent density functional theory (TDDFT) or time-dependent nonequilibrium Green’s functions (TDNEGF) with Jefimenko solutions of the Maxwell equations.
• Our solutions make it possible to predict (and doubly confirm) a new effect (charge current pumping by ultrafast demagnetization), while concurrently explaining the microscopic origin of conjectured interlayer spin current.
Interdisciplinary Research Group (IRG): Hybrid Quantum Materials with Emergent Terahertz Functionalities (HQ-METs)
For more information: Phys. Rev. B 111, L140415 (2025), Phys. Rev. Lett. 133, 136704 (2024), Phys. Rev. B 110, L060410 (2024)
