February 5 at 2:00 pm (Paris time)
Room Charpak, entrance building, ground floor
Surface plasmonic cavities at Terahertz frequencies : ultrasmall, chiral and more
I will present our work on the development of cavities and metamaterials operating in the Terahertz (THz) frequency range, using a surface plasmonic mechanism for light confinement. This approach enables the confinement of THz photons to volumes up to 10⁻⁸ times smaller than the free-space diffraction limit [1]. In this extreme regime, the cavities approach the ultimate spatial scale permitted by plasmonics, where novel phenomena such as nonlocal light–matter interactions begin to emerge. I will discuss how the broad tunability of THz surface plasmons through external parameters enables advanced engineering of the cavity fields, including the realization of chiral fields [2] and temporally engineered cavity fields, demonstrated through the recent realization of a photonic time crystal [3]. Overall, the plasmonic metamaterial approach offers a versatile route to synthesizing free-space and cavity fields at THz frequencies with full control over their spatial, temporal, and spin–orbit degrees of freedom.
[1] I. Aupiais et al. Nature Communications, 14(1), 2023.
[2] I. Aupiais et al. ACS Photonics, 11(10), 2024.
[3] T. Guo et al. arXiv 2510.02845

