Floquet Prethermalization with Lifetime Exceeding 90 s in a Bulk Hyperpolarized Solid

Area of Science:

• Quantum physics
• Solid-state physics
• Materials science

Background:

• Floquet engineering creates exotic states of matter using periodic driving.
• Nuclear spins in solids typically have short coherence times, limiting their use in quantum technologies.
• Diamond's ^{13}C nuclei offer a promising platform for quantum applications due to their long-range interactions.

Purpose of the Study:

• To investigate the creation and properties of long-lived Floquet prethermal states in a solid-state system.
• To demonstrate pulsed spin-lock control for extending the lifetime of nuclear spins.
• To explore the thermalization dynamics of these prethermal states and their potential for quantum sensing.

Main Methods:

• Utilizing optically hyperpolarized ^{13}C nuclei in diamond at room temperature.
• Applying pulsed spin-lock Floquet control to precessing nuclear spins.
• Continuous spin interrogation over extended periods (minutes) with high signal-to-noise ratio.

Main Results:

• Observation of long-lived Floquet prethermal states with lifetimes (T_{2}^{'}) of approximately 90.9 seconds.
• Achieving a >60,000-fold extension of nuclear spin lifetimes compared to free induction decay.
• Identifying four distinct regimes of thermalization dynamics, from transient processes to long-time heating.
• Demonstrating continuous interrogation of spins over ~10 minutes using ~5.8×10^6 control pulses.

Conclusions:

• Floquet control can create remarkably stable prethermal states in bulk solids.
• Extended prethermal lifetimes and continuous spin interrogation open new avenues for quantum sensing.
• This work highlights the potential of Floquet engineering in dilute, low-sensitivity nuclear spin systems.