Confinement of Tamm Modes in the THz Spectral Range

Electromagnetic resonators, based on optical cavities or electronic circuits, are fundamental components for enhancing and controlling light-matter interactions. THz Tamm cavities, which consist of a ditributed Bragg reflector (DBR) with a metallic mirror deposited on top, represent a particularly promising platform due to the control of the cavity mode by patterning the metal layer. For instance, subwavelength metal structuration has enabled fine frequency tuning and polarization sensitivity in THz Tamm cavities [1], while patterning metallic layer into an LC metamaterial has provided high Q factors associated with deep-subwavelength mode volumes [2]. To exploit these THz resonators for single photon THz devices and for ultrastrong THz light-matter coupling with high coherence in the few to single electron regime, it is essential to confine the mode spatially in all directions and also optimize coupling between the THz resonators and free-space THz beams.