Origin of the Acoustic Bandgaps in Hypersonic Colloidal Phononics: The Role of the Elastic Impedance

Cang Y, Sainidou R, Rembert P, Magnabosco G, Still T, Vogel N, Graczykowski B, Fytas G (2022)

Publication Type: Journal article

Publication year: 2022

Journal

Journal of Physical Chemistry B American Chemical Society

DOI: 10.1021/acs.jpcb.2c03923

Abstract

How phonons propagate in nanostructures determines the flow of elastic and thermal energy in dielectric materials. However, a reliable theoretical prediction of the phonon dispersion relation requires experimental verification both near to and far from the Brillouin zone of the nanostructure. We report on the experimental hypersonic phonon dispersion of hard (SiO2) and soft (polymer) fcc colloidal crystals infiltrated in liquid polydimethylsiloxane with different elastic impedance contrast using Brillouin light spectroscopy. We discuss the distinct differences with first-principles full elastodynamic calculations involving a multiple-scattering theory. Interparticle contacts strongly impact the long-wavelength speed of sound and the nature of the particle vibration resonance-induced hybridization hypersonic bandgap. The absence of the order-induced Bragg bandgap in SiO2 and its presence in soft opals cannot be fully accounted for by the theory, limiting its predictive power. Bridging the elasticity of the two colloidal crystals with suitable SiO2 core-shell (polymer) particles reveals an unprecedented crossover behavior in the dispersion relation. In view of many conversational parameters, the control tuning of phonon propagation in soft matter-based hypersonic phononics remains challenging.

Authors with CRIS profile

Giulia Magnabosco Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik Nicolas Vogel Professur für Partikelsynthese

Involved external institutions

Max-Planck-Institut für Polymerforschung (MPI-P) / Max Planck Institute for Polymer Research DE Germany (DE) Université de Caen Basse-Normandie FR France (FR)

How to cite

APA:

Cang, Y., Sainidou, R., Rembert, P., Magnabosco, G., Still, T., Vogel, N.,... Fytas, G. (2022). Origin of the Acoustic Bandgaps in Hypersonic Colloidal Phononics: The Role of the Elastic Impedance. Journal of Physical Chemistry B. https://dx.doi.org/10.1021/acs.jpcb.2c03923

MLA:

Cang, Yu, et al. "Origin of the Acoustic Bandgaps in Hypersonic Colloidal Phononics: The Role of the Elastic Impedance." Journal of Physical Chemistry B (2022).

BibTeX: Download