Semiconductor Quantum Information Device Research Team
Principal Investigator
| PI Name | Seigo Tarucha | ||||||||||||||||||||||||||||||
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| Degree | D.Eng. | ||||||||||||||||||||||||||||||
| Title | Team Leader | ||||||||||||||||||||||||||||||
| Brief Resume |
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Outline
We perform research and development of electron (or hole) spin based quantum computing with silicon quantum dots. Study on silicon quantum computing has been motivated by advantages of compatibility with existing semiconductor device integration technology and capability of high-temperature (> 1 Kelvin) operation. We demonstrate that manipulation of quantum coherence and entanglement of silicon spin qubits in semiconductor nanostructures and superconducting nano-scale junctions is useful as elemental technology of information processing and develop relevant quantum logic calculation methods, advanced quantum architectures, qubit devices having compatibility with integration technology.
Research Fields
Physics, Engineering
Keywords
Quantum computer
Qubit
Quantum dots
Quantum devices
Spin control
Results
Realization of high-accuracy two-spin exchange operation for spin qubits in silicon
Silicon quantum computer which utilizes electron spin in quantum dots is expected to suit implementation of large-scale quantum computer, because it has the huge head start of being able to operate at high temperature (>1K) and apply the semiconductor manufacturing techniques used for conventional electronics.
To execute quantum computing it is necessary to operate not only single qubits but also two qubits. To date high-accuracy qubit operation has been demonstrated for single spins but not yet for two spins. This is because of influences from electrical noise arising from charge impurities.
We have realized high-accuracy two-spin operation using a qubit that employs the spins of two electrons (| > and | >) in a silicon double quantum dot (Fig. A). We have developed a new method to minimize the influence from the electrical noise and achieved spin exchange operation with 99.6% accuracy, the highest ever reported (Fig. B).
Fig. A Electron micrograph of the Si triple quantum dot device. The double quantum dot in red and blue is used for experiment.
Fig. B Rabi oscillation measured for the exchange of the two two-spin states, |↑↓> and |↓↑>.
Members
Seigo Tarucha |
Team Leader | tarucha[at]riken.jp |
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