We are delighted to announce that third year PGR Benjamin Pearce has won the Month 25 Presentation Prize- a £50 Amazon voucher. The Month 25 presentations are given each October, where the PGRs give a presentation on their work to date and feedback scores are given by their peers. Ben’s presentation was titled ‘Mode Interference and Directional Acoustic Stop Bands in Solid-Fluid Superlattices’. Please find the abstract below.
‘Mode Interference and Directional Acoustic Stop Bands in Solid-Fluid Superlattices’
Whilst there is a large amount of work on one-dimensional phononic crystals (superlattices) consisting of alternating layers of solid materials, there is comparatively little investigation of the properties of the equivalent solid/fluid system. These systems are predicted to exhibit a directional transmission response not available to solid/solid systems. This response stems from an interference between the symmetric and anti-symmetric modes of a submerged plate. This effect can lead to pronounced, angularly dependent reductions in transmission, for even a single solid layer submerged in fluid [1,2]. Extending this system from a single plate to a multilayer structure offers an interesting avenue for phononic crystal design . Existing work largely neglects to consider the interaction of this interference with the Bragg modes of a such a periodic structure. Here we present a numerical and theoretical consideration of the effects of this interaction and how the choice of crystal geometry offers routes for the creation of large bandwidth directional stop bands.
 M. Seiji, “Phononic Bandgaps Pecuiar to Solid-Fluid Superlattices,” Jpn. J. Appl. Phys, 2015.
 Z. Sai, X. Bai-qiang and C. Wenwu, “Controlling The Angle Range in Acoustics Low-Frequency
Forbidden Transmission In Solid-Fluid Superlattice,” J. Appl. Phys, 2018.
 S. Zhang, Z. Y, L. Wei, G. Hu, X. Bai-qiang and C. Wenwu, “Low Frequency Forbidden Bandgap
Engineering Via A Cascade of Multiple 1D Superlattices,” J. Appl. Phys, 2018.