Fig. 2: Omnidirectional reflection of the metagrating.
From: Realization of ultrathin waveguides by elastic metagratings
a Simulated transmittance |t| and reflection phase φ at 15 kHz as a function of the incident angle θi. b Simulated transmittance |t| of the supercell composed by cell Ι and cell ΙΙ as functions of θi and the operating frequency f. c Simulated phase difference \({\Delta \phi ={\phi }_{{{{{{\rm{I}}}}}}}-\phi }_{{{{{{\rm{II}}}}}}}\) of the two unit-cells as a function of f. d Nearly total reflections are numerically observed for incident angels of 0°,30°,60°, respectively. Theoretical loci are plotted as black arrows. e Sample of a triangle-shaped omnidirectional isolator enclosed by the proposed metagratings. f Experimentally measured (EXP) energy field when a point source S1 is placed outside the enclosed region. g The measured (EXP) energy field when a point source S2 is located inside the enclosed region. h Experimental (EXP) and simulated (FEM) distributions of normalized energy (equivalent to the square of the displacement amplitude |w|2) along the dashed yellow line in (g).
