Figure 4: Transmission measurements.
From: Non-reciprocal and highly nonlinear active acoustic metamaterials
Time (top) and frequency (bottom) measurements of the wave transmitted through the unit cell in three cases: cell unpowered (dashed line), cell powered in the forward, transparent orientation (solid black) and cell powered in the reverse, opaque orientation (solid light red). The grey shaded region represents the time window ΔT used to compute the isolation factor F. The measurements were repeated three times and each time the results were virtually identical.
