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Published on: June 3, 2015
Two-qubit logic and teleportation with mobile spin qubits in silicon
Y Matsumoto1, M De Smet1, L Tryputen2
1QuTech and Kavli Institute of Nanoscience, Delft University of Technology, Delft, The Netherlands.
Nature
|May 6, 2026
Summary
Researchers demonstrate two-qubit quantum gates on mobile electron spins in a semiconductor. This breakthrough achieves high fidelity, paving the way for reconfigurable quantum processors and non-local quantum information processing.
Area of Science:
- Quantum Computing
- Solid-State Physics
- Quantum Information Science
Background:
- Quantum computing scalability relies on high-fidelity operations and flexible qubit connectivity.
- Mobile qubits offer dynamic reconfiguration of qubit arrays for adaptable quantum processors.
- Previous work showed coherent shuttling of electron spins in solid-state platforms.
Purpose of the Study:
- To investigate the feasibility of performing quantum gates directly on mobile electron spins.
- To demonstrate two-qubit operations and quantum state teleportation using mobile spin qubits in a semiconductor device.
Main Methods:
- Utilized a semiconductor device with travelling potential minima to shuttle two electron spins.
- Performed two-qubit gate operations by controlling the spatial separation of the mobile spins.
- Implemented conditional post-selected quantum state teleportation between spatially separated mobile qubits.
Main Results:
- Achieved an average two-qubit gate fidelity of approximately 99% by shuttling spins 120 nm each.
- Demonstrated quantum state teleportation between qubits separated by 320 nm with an average gate fidelity of 87%.
- Showcased tunable interaction strength based on the spatial separation of mobile electron spins.
Conclusions:
- Successfully performed high-fidelity two-qubit gates and quantum state teleportation on mobile electron spins.
- Mobile spin qubits in semiconductors show significant potential for non-local quantum information processing.
- Operations on mobile qubits are expected to be a key feature in future large-scale semiconductor quantum processors.
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