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arXiv · 2311.01370

Quantum Sensing with Topological-Paired Bound States

Tao Zhang·Peng Xu·Jiazhong Hu·Xingze Qiu
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Abstract

We present an efficient and robust protocol for quantum-enhanced sensing using a single qubit in the topological waveguide system. Our method relies on the topological-paired bound states, which are localized near the qubit and can be effectively regarded as a two-level system. Through the lens of Bayesian inference theory, we show that the sensitivity can reach the Heisenberg limit across a large field range. Inheriting from the topological robustness of the waveguide, our sensing protocol is robust against local perturbations. Besides, our sensing protocol utilizes a product state as the initial state, which can be easily prepared in experiments. We expect this approach would pave the way toward robust topological quantum sensors based on near-term quantum platforms such as superconducting qubits and Rydberg arrays.

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Tao Zhang, Peng Xu, Jiazhong Hu, Xingze Qiu. 2023-11-02. Quantum Sensing with Topological-Paired Bound States. https://doi.org/10.1088/1367-2630%2Fadd8b0

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