Terahertz Spin-Light Coupling in Proximitized Dirac Materials

TL;DR

This paper uncovers a strong terahertz spin-light interaction in 2D Dirac materials caused by proximity effects, enabling new spin control and detection methods for quantum devices.

Contribution

It introduces a mean-field and quantum-mechanical theory for THz spin-light coupling in proximitized 2D Dirac materials, highlighting novel spin-pseudospin dynamics and their effects.

Findings

Enhanced THz light absorption in proximitized graphene.

Distinctive polarization structures enabling spin control.

Potential applications in THz detection and spin-based quantum devices.

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.