  This study examines the Braggs bandgap and its mechanical tuning in a
stretch-buckled kirigami sheet with "zig-zag" distributed parallel cuts. When
stretched beyond a critical threshold, the kirigami buckles out-of-plane and
generates a 3D periodic architecture. Our theoretical calculation, numerical
simulation, and experiments confirm the transverse elastic wave propagation
bandgaps and their correlation to stretching. This result opens an avenue of
using kirigami as a simple and effective approach for creating and adapting
periodicity for wave propagation control.
