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Electrically controlling single-spin qubits in a continuous microwave field.

ABSTRACT: Large-scale quantum computers must be built upon quantum bits that are both highly coherent and locally controllable. We demonstrate the quantum control of the electron and the nuclear spin of a single (31)P atom in silicon, using a continuous microwave magnetic field together with nanoscale electrostatic gates. The qubits are tuned into resonance with the microwave field by a local change in electric field, which induces a Stark shift of the qubit energies. This method, known as A-gate control, preserves the excellent coherence times and gate fidelities of isolated spins, and can be extended to arbitrarily many qubits without requiring multiple microwave sources.

SUBMITTER: Laucht A

PROVIDER: S-EPMC4640634 | biostudies-literature | 2015 Apr

REPOSITORIES: biostudies-literature

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Electrically controlling single-spin qubits in a continuous microwave field.

Laucht Arne A Muhonen Juha T JT Mohiyaddin Fahd A FA Kalra Rachpon R Dehollain Juan P JP Freer Solomon S Hudson Fay E FE Veldhorst Menno M Rahman Rajib R Klimeck Gerhard G Itoh Kohei M KM Jamieson David N DN McCallum Jeffrey C JC Dzurak Andrew S AS Morello Andrea A

Science advances 20150410 3

Large-scale quantum computers must be built upon quantum bits that are both highly coherent and locally controllable. We demonstrate the quantum control of the electron and the nuclear spin of a single (31)P atom in silicon, using a continuous microwave magnetic field together with nanoscale electrostatic gates. The qubits are tuned into resonance with the microwave field by a local change in electric field, which induces a Stark shift of the qubit energies. This method, known as A-gate control, ...[more]

PMID: 26601166

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