Loss-induced modal selection by a resistive wiremesh

This work examines the impact of local losses produced by a resistive wiremesh on the modes of an acoustic cavity. In the one-dimensional case, we demonstrate the ability to selectively affect the modes, ranging from being completely unaffected by the wiremesh to being fully absorbed by it. This effect can be used to filter the cavity modes. In the two-dimensional case, higher order modes are considered and we discuss the effect of wiremesh tilt on the cavity modes. A new type of mode that is localized on the wiremesh with a purely imaginary eigenfrequency has been identified. These findings show that wiremeshes are ultrabroadband lossy metasurfaces offering a straightforward way to explore passive non-Hermitian systems.