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arXiv · 2410.21614

Terahertz Spin-Light Coupling in Proximitized Dirac Materials

Konstantin S. Denisov·Igor V. Rozhansky·Sergio O. Valenzuela·Igor Žutić
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Abstract

The two-dimensional (2D) materials are highly susceptible to the influence of their neighbors, thereby enabling the design by proximity phenomena. We reveal a remarkable terahertz (THz) spin-light interaction in 2D Dirac materials that arises from magnetic and spin-orbital proximity effects. The dynamical realization of the spin-charge conversion, the electric dipole spin resonance (EDSR), of Dirac electrons displays distinctive THz features, upon emerging spin-pseudospin proximity terms in the Hamiltonian. To capture the effect of fast pseudospin dynamics on the electron spin, we develop a mean-field theory and complement it with a quantum-mechanical treatment. As a specific example, we investigate the THz response of a single graphene layer proximitized by a magnetic substrate. Our analysis demonstrates a strong enhancement and anomalous polarization structure of the THz-light absorption which can enable THz detection and efficient generation and control of spins in spin-based quantum devices. The identified coupled spin-pseudospin dynamics is not limited to EDSR and may influence a broad range of optical, transport, and ultrafast phenomena.

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Konstantin S. Denisov, Igor V. Rozhansky, Sergio O. Valenzuela, Igor Žutić. 2024-10-28. Terahertz Spin-Light Coupling in Proximitized Dirac Materials. https://doi.org/10.1103/physrevb.109.l201406

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