Inerter-based elastic metamaterials for band gap at extremely low frequency

We reveal the unique and fundamental advantage of inerter-based elastic metamaterials by a comparative study among different configurations. When embedded inerter is connected to matrix material on both ends, metamaterial shows definite superiority in forming band gap ultra-low frequency - equivalently ultra-long wavelength regime, where unit cell size can be four or more orders magnitude smaller than operating wavelength. In addition, our parametric studies one two dimensions pave way towards designing next-generation for structural vibration mitigation.