Fig. 6: Applications for metasurfaces with EP of the scattering matrix.
From: Resonant and scattering exceptional points in non-Hermitian metasurfaces
a EP metasurface with 2π phase transition127. Left panel: Perspective and (bottom) top view of the metasurface designed in reflection. Right panel: Simulated CP conversion coefficients \({r}_{+-}\). b Asymmetric transmission EP metasurface131. Left panel: Variation of the transmission matrix components in the circularly polarized basis when passing over the metasurface. Right panel: Transmission spectrum of the metasurface. c Metasurface with chiral EP enhanced asymmetry polarization133. Left panel: Parameter space surrounding EP on the Riemann surface. Right panel: Variation of the eigentransmission magnitude and eigenpolarization ellipse angle along the cyclic variation. d Metal–graphene hybrid metasurface with switchable scattering characteristics134. Left panel: Magnitudes, phase, and polarization eigenstates for the eigenvalues of the S-matrix obtained at different EF values. Right panel: Polarization eigenstates are represented on the Poincare ́ sphere. a, d reprinted with permission from ref. 127. and ref. 134, respectively. b from ref. 131. permitted under the Creative Commons license CC BY 4.0. c from ref. 133. permitted under the Creative Commons CC BY license.
