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arXiv · 2106.15690

Non-Hermitian many-body topological excitations in interacting quantum dots

Timo Hyart·Jose L. Lado
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Abstract

Quantum dots are one of the paradigmatic solid-state systems for quantum engineering, providing an outstanding tunability to explore fundamental quantum phenomena. Here we show that non-Hermitian many-body topological modes can be realized in a quantum dot chain by utilizing a gate-tunable modulation of dissipation, and they emerge purely because of the non-Hermiticity. By exactly solving the non-Hermitian interacting description both with exact diagonalization and tensor-networks, we demonstrate that these topological modes are robust even in the presence strong interactions, leading to a strongly correlated topological many-particle state. Our results put forward quantum dot arrays as a platform for engineering non-Hermitian many-body topological modes, and highlight the resilience of non-Hermitian topology to electronic interactions.

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Timo Hyart, Jose L. Lado. 2021-06-29. Non-Hermitian many-body topological excitations in interacting quantum dots. https://doi.org/10.1103/physrevresearch.4.l012006

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