Anisotropic lattice expansion of three-dimensional colloidal crystals and its impact on hypersonic phonon band gaps. uri icon

abstract

  • We report anisotropic expansion of self-assembled colloidal polystyrene-poly(dimethylsiloxane) crystals and its impact on the phonon band structure at hypersonic frequencies. The structural expansion was achieved by a multistep infiltration-polymerization process. Such a process expands the interplanar lattice distance 17% after 8 cycles whereas the in-plane distance remains unaffected. The variation of hypersonic phonon band structure induced by the anisotropic lattice expansion was recorded by Brillouin measurements. In the sample before expansion, a phononic band gap between 3.7 and 4.4 GHz is observed; after 17% structural expansion, the gap is shifted to a lower frequency between 3.5 and 4.0 GHz. This study offers a facile approach to control the macroscopic structure of colloidal crystals with great potential in designing tunable phononic devices.

published proceedings

  • Phys Chem Chem Phys

author list (cited authors)

  • Wu, S., Zhu, G., Zhang, J. S., Banerjee, D., Bass, J. D., Ling, C., & Yano, K.

citation count

  • 8

complete list of authors

  • Wu, Songtao||Zhu, Gaohua||Zhang, Jin S||Banerjee, Debasish||Bass, Jay D||Ling, Chen||Yano, Kazuhisa

publication date

  • January 2014