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arXiv · 2001.04969

Non-Hermitian band topology and skin modes in active elastic media

Colin Scheibner·William T. M. Irvine·Vincenzo Vitelli
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Abstract

Solids built out of active components can exhibit non-reciprocal elastic coefficients that give rise to non-Hermitian wave phenomena. Here, we investigate non-Hermitian effects present at the boundary of two-dimensional active elastic media obeying two general assumptions: their microscopic forces conserve linear momentum and arise only from static deformations. Using continuum equations, we demonstrate the existence of the non-Hermitian skin effect in which the boundary hosts an extensive number of localized modes. Furthermore, lattice models reveal non-Hermitian topological transitions mediated by exceptional rings driven by the activity level of individual bonds.

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Colin Scheibner, William T. M. Irvine, Vincenzo Vitelli. 2020-01-14. Non-Hermitian band topology and skin modes in active elastic media. https://doi.org/10.1103/physrevlett.125.118001

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