Phys.org March 31, 2023
Among the many qubit platforms, spin qubits in silicon quantum dots are promising for large-scale integration along with their nanofabrication capability. However, linking distant silicon quantum processors is challenging as two-qubit gates in spin qubits typically utilize short-range exchange coupling, which is only effective between nearest-neighbor quantum dots. Coherent shuttling of a spin qubit enables efficient switching of the exchange coupling with an on/off ratio exceeding 1000, while preserving the spin coherence by 99.6% for the single shuttling between neighboring dots. An international team of researchers (Japan, the Netherlands) has demonstrated a two-qubit controlled-phase gate with a fidelity of 93%, assessed via randomized benchmarking. Combination of their technique and a phase coherent shuttling of a qubit across a large quantum dot array will provide feasible path toward a quantum link between distant silicon quantum processors, a key requirement for large-scale quantum computation… read more. Open Access TECHNICAL ARTICLE
RIKEN researchers have linked two distant qubits… Credit: 2023 RIKEN Center for Emergent Matter Science.