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arXiv · 1904.02771

Topological Insulators by Topology Optimization

Rasmus E. Christiansen·Fengwen Wang·Ole Sigmund
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Abstract

An acoustic topological insulator (TI) is synthesized using topology optimization, a free material inverse design method. The TI appears spontaneously from the optimization process without imposing requirements on the existence of pseudo spin-1/2 states at the TI interface edge, or the Chern number of the topological phases. The resulting TI is passive; consisting of acoustically hard members placed in an air background and has an operational bandwidth of $\approx$12.5\% showing high transmission. Further analysis demonstrates confinement of more than 99\% of the total field intensity in the TI within at most six lattice constants from the TI interface. The proposed design hereby outperforms a reference from recent literature regarding energy transmission, field confinement and operational bandwidth.

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Rasmus E. Christiansen, Fengwen Wang, Ole Sigmund. 2019-04-04. Topological Insulators by Topology Optimization. https://doi.org/10.1103/physrevlett.122.234502

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