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arXiv · 1809.08687

Chiral voltage propagation in a self-calibrated topolectrical Chern circuit

Tobias Hofmann·Tobias Helbig·Ching Hua Lee·Martin Greiter·Ronny Thomale
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Abstract

We propose an electric circuit array with topologically protected uni-directional voltage modes at its boundary. Instead of external bias fields or floquet engineering, we employ negative impedance converters with current inversion (INICs) to accomplish a non-reciprocal, time-reversal symmetry broken electronic network we call topolectrical Chern circuit (TCC). The TCC features an admittance bulk gap fully tunable via the resistors used in the INICs, along with a chiral voltage boundary mode reminiscent of the Berry flux monopole present in the admittance band structure. The active circuit elements in the TCC can be calibrated to compensate for dissipative loss.

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Tobias Hofmann, Tobias Helbig, Ching Hua Lee, Martin Greiter, Ronny Thomale. 2018-09-23. Chiral voltage propagation in a self-calibrated topolectrical Chern circuit. https://doi.org/10.1103/physrevlett.122.247702

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