Skip to Main content Skip to Navigation
Journal articles

Abnormal topological refraction into free medium at sub-wavelength scale in valley phononic crystal plates

Abstract : In this work we propose a topological valley phononic crystal plate and we extensively investigate the refraction of valley modes into the surrounding homogeneous medium. This phononic crystal includes two sublattices of resonators (A and B) modeled by mass-spring systems. We show that two edge states confined at the AB/BA and BA/AB type domain walls exhibit different symmetries in physical space and energy peaks in the Fourier space. As a result, distinct refraction behaviors, especially through an armchair cut edge, are observed. On the other hand, the decay depth of these localized topological modes, which is found to be solely determined by the relative resonant strength between the scatterers, significantly affects the refraction patterns. More interestingly, the outgoing traveling wave through a zigzag interface becomes evanescent when operating at deep subwavelength scale. This is realized by tuning the average resonant strength. We show that the evanescent modes only exist along a particular type of outlet edge and that they can couple with both topological interface states. We also present a near-ideal monopole and a dipole emitter based on our phononic structure.
Document type :
Journal articles
Complete list of metadata
Contributor : Hal Sorbonne Université Gestionnaire Connect in order to contact the contributor
Submitted on : Thursday, May 6, 2021 - 5:20:25 PM
Last modification on : Tuesday, October 19, 2021 - 11:10:48 AM
Long-term archiving on: : Saturday, August 7, 2021 - 7:36:06 PM


 Restricted access
To satisfy the distribution rights of the publisher, the document is embargoed until : 2021-11-06

Please log in to resquest access to the document



Linyun Yang, Kaiping Yu, Bernard Bonello, Bahram Djafari-Rouhani, Wei Wang, et al.. Abnormal topological refraction into free medium at sub-wavelength scale in valley phononic crystal plates. Physical Review B, American Physical Society, 2021, 103 (18), pp.184303. ⟨10.1103/PhysRevB.103.184303⟩. ⟨hal-03219859⟩



Record views