Researchers at Delft University of Technology have demonstrated for the first time that two-qubit logic gates can be performed on mobile electron spins traveling across a silicon chip, a development published in Nature on May 6, 2026, that could reshape the path toward scalable quantum processors.
Moving Qubits, New Possibilities
The team, led by Lieven Vandersypen at QuTech, used a technique called conveyor-mode shuttling — in which phase-shifted electrical signals applied to gate electrodes create a traveling-wave potential that carries individual electrons across the chip inside moving quantum dots. Rather than keeping qubits fixed in place and routing information through complex wiring, the approach physically transports the quantum information carriers themselves.
“What if you could make two electron spins interact simply by moving them towards each other, each propagated in a traveling-wave potential minimum?” Vandersypen wrote in a post describing the work. The researchers achieved an average two-qubit gate fidelity of approximately 99 percent by tuning the interaction strength through spatial separation of the electrons. They also implemented quantum state teleportation between spatially separated qubits with an average gate fidelity of 87 percent.
Why It Matters for Scaling
The architecture addresses one of the central challenges in quantum computing: connecting distant qubits without an impractical tangle of control lines. Mobile qubits enable dynamic, reconfigurable connectivity patterns during operation, allow different quantum error correction codes to run on the same hardware, and permit dedicated functional zones for tasks like measurement or entanglement generation.
Crucially, the device is fabricated in isotopically purified silicon-germanium — materials compatible with standard semiconductor manufacturing processes. This compatibility with existing chip fabrication infrastructure distinguishes the approach from platforms requiring exotic materials or extreme optical setups.
A Crowded Field Advances
The Nature publication arrives amid a flurry of activity in silicon-based quantum computing. In April, QuTech researchers demonstrated programmable quantum circuits across six silicon spin qubits, and a separate team showed new spin-qubit readout methods that could reduce wiring complexity in larger processors. Vandersypen presented the shuttling paradigm at a Princeton Quantum Colloquium on April 27.
The researchers expect that operations on mobile qubits “will become a universal feature of future large-scale semiconductor quantum processors”.
