• Physics 14, s132
Researchers have saved a Floquet system in a prethermal state for a document size of time.
Periodically driven systems provide a platform for investigating quantum phenomena and exotic states of matter (see Viewpoint: Time Crystals in Open Systems). These phenomena are best to review when these so-called Floquet methods are in a nonequilibrium “prethermal” regime. But finally, the vitality delivered by the periodic driver distributes via the system, heating it to equilibrium and washing away details about these attention-grabbing quantum states. Now, in a Floquet system based mostly on nuclear spins surrounding a diamond defect, William Beatrez, on the University of California, Berkeley, and colleagues have managed to stave off thermalization for the longest time but . The achievement widens the window via which physicists can observe prethermal and thermalization dynamics and will result in high-sensitivity magnetometers and spin sensors.
To generate a Floquet state, the researchers polarized a diamond nitrogen-vacancy heart by pumping it with a laser. They then used microwaves to switch this polarization to surrounding carbon-13 nuclei, which unfold the polarization all through the remainder of the diamond through dipole-dipole coupling. Left alone, this state decays in round 1.5 ms. But by driving the system with radio-frequency pulses, the researchers induced a collective precession within the nuclear spins, prolonging the polarization lifetime greater than 60,000-fold. They measured this precession utilizing nuclear magnetic resonance.
Beatrez and colleagues say that the diploma to which their method extends the prethermal interval is stunning. Previous experiments utilizing ultracold atoms sustained the prethermal state for round 22,000 driving cycles; within the new experiment, it lasted for 1.6 million cycles. The group hopes that they will use this longer view to review nonequilibrium phenomena, resembling time-crystalline conduct.
Marric Stephens is a Corresponding Editor for Physics based mostly in Bristol, UK.
- W. Beatrez et al., “Floquet prethermalization with lifetime exceeding 90 s in a bulk hyperpolarized solid,” Phys. Rev. Lett. 127, 170603 (2021).