Phys.org September 12, 2024
The nuclear spin presents opportunities for quantum experiments with prolonged coherence times. Electron spin resonance (ESR) combined with scanning tunnelling microscopy (STM) provides a bottom-up platform to study the fundamental properties of nuclear spins of single atoms on a surface. However, access to the time evolution of nuclear spins remained a challenge. An international team of researchers (The Netherlands, Germany) developed an experiment resolving the nanosecond coherent dynamics of a hyperfine-driven flip-flop interaction between the spin of an individual nucleus and that of an orbiting electron. They used the unique local controllability of the magnetic field emanating from the STM probe tip to bring the electron and nuclear spins in tune. Subsequently, they polarized both spins through scattering of tunnelling electrons and measured the resulting free evolution of the coupled spin system. The latter revealed a complex pattern of multiple interfering coherent oscillations, providing unique insight into hyperfine physics on a single atom level… read more. Open Access TECHNICAL ARTICLE
Single atom nuclear polarization. Credit: Nature Communications volume 15, Article number: 7951 (2024)