Quantum coherence control at near 1000 K

TL;DR

This paper demonstrates the ability to control quantum coherence of nitrogen-vacancy center spins in nanodiamonds at temperatures near 1000 K, enabling high-temperature quantum sensing applications.

Contribution

It introduces a novel method for high-temperature quantum coherence control using laser heating and cooling of nanodiamonds, surpassing previous temperature limits.

Findings

Quantum coherence control achieved at ~1000 K

Observation of magnetic phase transition at 615 K

Enables high-temperature nano-thermometry and nano-magnetometry

Abstract

Quantum coherence control usually requires extremely low temperature environments. Even for spins in diamond, a remarkable exception, the coherence signal is lost as temperature approaches 700 K. Here we demonstrate quantum coherence control of the electron spins of nitrogen-vacancy centers in nanodiamonds at temperatures near 1000 K. The scheme is based on initialization and readout of the spins at room temperature and control at high temperature, which is enabled by pulse laser heating and rapid diffusion cooling of nanodiamonds on amorphous carbon films. Using high-temperature spin control, we observe the magnetic phase transition of a single nickel nanoparticle at about 615 K. This work enables nano-thermometry and nano-magnetometry in the high-temperature regime.