Tunable spatially and temporally ultrasound propagation in 3D microscale acoustic or elastic wave metamaterial

https://news.mit.edu/2024/tunable-ultrasound-propagation-microscale-metamaterials-1120

"lightweight/ strong, at high frequencies... positioning microscale spheres within metamaterial lattice, leading to wave guiding or focusing responses... nondestructive, high-throughput laser-ultrasonics... acoustic demultiplexer... using simple geometrical changes, expands tunable dynamics... simple geometric changes  in mass/ stiffness... 1 constituent material and 1 base 3D geometry... extreme-condition ultrasound: imaging including medical, information transmission, mechanical computing"