Ultra-thin metasurfaces with a specific multi-resonant response can enable simultaneously arbitrarily strong and arbitrarily broadband dispersion compensation, pulse (de)chirping, & compression or broadening with low loss.
This work overcomes the fundamental limitations of both conventional non-resonant approaches (bulky) & modern singly resonant metasurfaces (narrowband) for quadratic phase manipulations of electromagnetic signals, which is especially relevant to high-speed optical communication.
- The nonuniform trains of electric and magnetic resonances that allow to completely control phase delay, group delay, and chirp are rigorously derived & the fundamental limitations revealed.
- We construct practical, physically realizable approximations by finite sequences of linear resonances & rigorously quantify the associated error. This works in either transmission or reflection.
Article Link: https://doi.org/10.1103/PhysRevB.107.165408