Nanoscale ‘conveyor belt’ teleports quantum state of electron

Practical quantum computers will require many millions of interacting quantum bits (qubits). This could, in principle, be achieved by using a property of electrons called spin as a qubit. Spin qubits must be located very close together, and the physical challenge of wiring them to the bulky external control hardware has so far limited quantum circuits to a dozen or fewer electron spin qubits¹. But now, writing in Nature, Matsumoto et al.² report a potential solution: a logical circuit in which two distant spin qubits are brought together using a silicon ‘conveyor belt’. This set-up promises more flexibility, less crowding and fewer errors than static spin-qubit circuits offer. The authors demonstrate their device by ‘teleporting’ a quantum state across the device, a distance of 320 nanometres.