Overview

• UNSW researchers report in Science that they created entanglement between two phosphorus nuclear spins separated by about 20 nanometres in ultra‑pure silicon.
• The interaction was mediated by electrons using a geometric gate, removing the need for both nuclei to share the same electron.
• The demonstration targets a long‑standing connectivity bottleneck for nuclear‑spin qubits, which previously offered long coherence times and low error rates but limited linking options.
• The chip used implanted phosphorus from the University of Melbourne team and isotopically engineered silicon supplied by Keio University.
• The group describes the method as compatible with existing semiconductor manufacturing, with scaling to larger arrays and longer links identified as the next engineering challenge.