Polarization independent lattice-coupled terahertz toroidal excitation

The toroidal dipole excitation is an important field for metamaterial research because of their low-loss attribute. In this study, we demonstrate numerically and experimentally, a unique polarization independent terahertz that modulates broad resonance into sharp mode by coupling the inherent to lattice metasurface. advantage independence in metasurface enables lattice-coupled both transverse electric magnetic modes incident radiation. interaction two dark results significant enhancement quality factor at point matching. Such lattice-matched excitation-based device has potential impact development low loss component ultrasensitive sensors, equipment, slow light devices enhanced matter interaction.