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arXiv · 2212.13880

Improving Metrology with Quantum Scrambling

Zeyang Li·Simone Colombo·Chi Shu·Gustavo Velez·Saúl Pilatowsky-Cameo·Roman Schmied·Soonwon Choi·Mikhail Lukin·Edwin Pedrozo-Peñafiel·Vladan Vuletić
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Abstract

Quantum scrambling describes the spreading of local information into many degrees of freedom in quantum systems. This provides the conceptual connection among diverse phenomena ranging from thermalizing quantum dynamics to models of black holes. Here we experimentally probe the exponential scrambling of a multi-particle system near a bistable point in phase space and utilize it for entanglement-enhanced metrology. We use a time-reversal protocol to observe a simultaneous exponential growth of both the metrological gain and the out-of-time-order correlator, thereby experimentally verifying the relation between quantum metrology and quantum information scrambling. Our experiments demonstrate that fast-scrambling dynamics capable of exponentially fast entanglement generation are useful for practical metrology, resulting in 6.8(4) dB gain beyond the Standard Quantum Limit.

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Zeyang Li, Simone Colombo, Chi Shu, Gustavo Velez, Saúl Pilatowsky-Cameo, Roman Schmied, Soonwon Choi, Mikhail Lukin, Edwin Pedrozo-Peñafiel, Vladan Vuletić. 2022-12-24. Improving Metrology with Quantum Scrambling. https://doi.org/10.1126/science.adg9500

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