On November 27 (Beijing Time), a research team helmed by Professor Wang Ya from the Spin Magnetic Resonance Laboratory at the University of Science and Technology of China (USTC), in partnership with the National Key Laboratory of Marine Precision Sensing Technology at Zhejiang University, achieved a landmark advancement in the realm of nanoscale quantum precision measurement. For the first time, they successfully accomplished entanglement-enhanced nanoscale single-spin detection amidst noisy conditions. The pertinent research findings were published online in the esteemed journal Nature, under the title “Entanglement-Enhanced Nanoscale Single-Spin Sensing.”

Electron spins, functioning as microscopic magnetic units, play a pivotal role in comprehending material properties and driving the progress of quantum technologies. However, the detection of individual spins is an arduous task due to the abundance of spins present in materials. Diamond nitrogen-vacancy (NV) color center quantum sensors have emerged as a crucial technological avenue for single-spin detection, owing to their nanoscale resolution and heightened sensitivity to magnetic fields.

Through years of expertise accumulation, the research team has honed high-precision spin quantum control techniques, along with developing core diamond quantum sensing devices and equipment. Moreover, they have established a comprehensive process flow encompassing over twenty steps and have mastered key processes. In this particular study, leveraging collaborative innovation in material preparation and quantum manipulation, the team pioneered an entanglement-enhanced nanoscale single-spin detection technology. This technology simultaneously enhances the sensitivity to microscopic magnetic signals and spatial resolution in solid-state systems.

This groundbreaking technology has yielded three significant advancements: Firstly, it has successfully distinguished and detected two adjacent “dark” electron spins. Secondly, it has elevated detection sensitivity to 3.4 times that of a single sensor in noisy environments. Thirdly, it enables real-time monitoring and active control of unstable spin signals. These findings not only underscore the advantages and potential of quantum entanglement in nanoscale sensing but also highlight the formidable capabilities of diamond quantum sensors as nanoscale magnetometers. They open up a new vista for atomic-level study of quantum materials and promise revolutionary research tools for fields such as condensed matter physics, quantum biology, and chemistry. Additionally, the related technologies lay a vital foundation for realizing room-temperature diamond-based quantum computing.