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arXiv · 2104.01988

Floquet prethermalization with lifetime exceeding 90s in a bulk hyperpolarized solid

William Beatrez·Otto Janes·Amala Akkiraju·Arjun Pillai·Alexander Oddo·Paul Reshetikhin·Emanuel Druga·Maxwell McAllister·Mark Elo·Benjamin Gilbert·Dieter Suter·Ashok Ajoy
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Abstract

We report the observation of long-lived Floquet prethermal states in a bulk solid composed of dipolar-coupled $^{13}$C nuclei in diamond at room temperature. For precessing nuclear spins prepared in an initial transverse state, we demonstrate pulsed spin-lock Floquet control that prevents their decay over multiple-minute long periods. We observe Floquet prethermal lifetimes $T_2'\approx$90.9s, extended >60,000-fold over the nuclear free induction decay times. The spins themselves are continuously interrogated for $\sim$10min, corresponding to the application of $\approx$5.8M control pulses. The $^{13}$C nuclei are optically hyperpolarized by lattice Nitrogen Vacancy (NV) centers; the combination of hyperpolarization and continuous spin readout yields significant signal-to-noise in the measurements. This allows probing the Floquet thermalization dynamics with unprecedented clarity. We identify four characteristic regimes of the thermalization process, discerning short-time transient processes leading to the prethermal plateau, and long-time system heating towards infinite temperature. This work points to new opportunities possible via Floquet control in networks of dilute, randomly distributed, low-sensitivity nuclei. In particular, the combination of minutes-long prethermal lifetimes and continuous spin interrogation opens avenues for quantum sensors constructed from hyperpolarized Floquet prethermal nuclei.

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William Beatrez, Otto Janes, Amala Akkiraju, Arjun Pillai, Alexander Oddo, Paul Reshetikhin, Emanuel Druga, Maxwell McAllister, Mark Elo, Benjamin Gilbert, Dieter Suter, Ashok Ajoy. 2021-04-05. Floquet prethermalization with lifetime exceeding 90s in a bulk hyperpolarized solid. https://doi.org/10.1103/physrevlett.127.170603

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