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arXiv · 2512.13294

Projected Optimal Sensors from Operator Orbits

Sooryansh Asthana·Yeshma Ibrahim·Norman Tze Wei Koo·Sai Vinjanampathy
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Abstract

We unify Ramsey, twist-untwist, and random quantum sensors using operator algebra and account for the Fisher scaling of various sensor designs. We illustrate how the operator orbits associated with state preparation inform the scaling of the sensitivity with the number of subsystems. Using our unified model, we design a novel set of sensors in which a projected ensemble of quantum states exhibits beyond-shot-noise metrological performance. We also show favorable scaling of Fisher information with decoherence models and loss of particles.

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Sooryansh Asthana, Yeshma Ibrahim, Norman Tze Wei Koo, Sai Vinjanampathy. 2025-12-15. Projected Optimal Sensors from Operator Orbits. https://arxiv.org/abs/2512.13294

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