Fig. 3: Enhanced coupling in a far-field cavity-waveguide phonon system.
From: Far-field phonon coupling in valley metamaterial circuits
a Normalized |uz| measured at locations on the sample as marked in Fig. 2a (Pure PnC, FFC, Inlet, Outlet), excited by a pulsed source centered at fc = 1.8 MHz. FFC spectrum (blue curve) shows peaks P1-P4 at 1.808, 1.867, 1.937 and 1.976 MHz, respectively. b Measured |uz| distributions at frequencies corresponding to P2-P4, together with the in-plane wave flux (bold arrows). Lines outline the waveguide, cavity path, and truncated terminal. c Simulated spectra showing FFC peaks P1-P4 (blue) and outlet dips D1-D4 (red) at 1.794, 1.843, 1.929 and 1.976 MHz. Insets show zoomed-in views of the outlet |uz| at D2-D4: numerical data are shown by the dotted lines, and theoretical results by the red solid lines. d Simulated uz distributions at frequencies corresponding to P2-P4 with in-plane energy flux (bold arrows).
