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arXiv · 2511.17749

Entanglement Witnesses of Condensation for Enhanced Quantum Sensing

Lillian I. Payne Torres·Irma Avdic·Anna O. Schouten·Olivia C. Wedig·Gregory S. Engel·David A. Mazziotti
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Abstract

Quantum phenomena such as entanglement provide powerful resources for enhancing classical sensing. Here, we theoretically show that collective entanglement of spin qubits, arising from a condensation of particle-hole pairs, can strongly amplify transitions between ground and excited spin states, potentially improving signal contrast in optically detected magnetic resonance. This collective state exhibits an $\mathcal{O}(\sqrt{N})$ enhancement of the transition amplitude with respect to an applied microwave field, where $N$ is the number of entangled spin qubits. We computationally realize this amplification using an ensemble of $N$ triplet spins with magnetic dipole interactions, where the largest transition amplitudes occur at geometries for which the condensation of particle-hole pairs is strongest. This effect, robust to noise, originates from the concentration of entanglement into a single collective mode, reflected in a large eigenvalue of the particle-hole reduced density matrix -- an entanglement witness of condensation analogous to off-diagonal long-range order, though realized here in a finite system. These results offer a design principle for quantum sensors that exploit condensation-inspired entanglement to boost sensitivity in spin-based platforms.

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Lillian I. Payne Torres, Irma Avdic, Anna O. Schouten, Olivia C. Wedig, Gregory S. Engel, David A. Mazziotti. 2025-11-21. Entanglement Witnesses of Condensation for Enhanced Quantum Sensing. https://arxiv.org/abs/2511.17749

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