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arXiv · 2201.02012

Compact localized boundary states in a quasi-1D electronic diamond-necklace chain

S. N. Kempkes·P. Capiod·S. Ismaili·J. Mulkens·L. Eek·I. Swart·C. Morais Smith
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Abstract

Zero-energy modes localized at the ends of one-dimensional (1D) wires hold great potential as qubits for fault-tolerant quantum computing. However, all the candidates known to date exhibit a wave function that decays exponentially into the bulk and hybridizes with other nearby zero-modes, thus hampering their use for braiding operations. Here, we show that a quasi-1D diamond-necklace chain exhibits a completely unforeseen type of robust boundary state, namely compact localized zero-energy modes that do not decay into the bulk. We theoretically engineer a lattice geometry to access this mode, and experimentally realize it in an electronic quantum simulator setup. Our work provides a general route for the realization of robust and compact localized zero-energy modes that could potentially be braided without the drawbacks of hybridization.

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S. N. Kempkes, P. Capiod, S. Ismaili, J. Mulkens, L. Eek, I. Swart, C. Morais Smith. 2022-01-06. Compact localized boundary states in a quasi-1D electronic diamond-necklace chain. https://doi.org/10.1007/s44214-023-00026-0

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