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Spin-photon interface and spin-controlled photon switching in a nanobeam waveguide
Alisa Javadi1, Dapeng Ding2, Martin Hayhurst Appel2
1Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark. javadi@nbi.ku.dk.
Nature Nanotechnology
|March 21, 2018
Summary
Researchers developed an efficient spin-photon interface using electron spins in quantum dots. This breakthrough enables optical control of quantum information, paving the way for quantum networks.
Area of Science:
- Quantum Information Science
- Quantum Optics
- Solid-State Physics
Background:
- Electron spin is a key candidate for quantum memory and quantum bits (qubits).
- Establishing quantum networks requires connecting spatially separated spin states.
- An integrated spin-photon interface is crucial for merging spin memory with photonic information transfer.
Purpose of the Study:
- To demonstrate an efficient and optically programmable interface between electron spins in quantum dots and photons.
- To leverage this interface for controlling quantum information transfer.
Main Methods:
- Utilized a quantum dot system to host electron spins.
- Developed a nanophotonic waveguide for photon interaction.
- Implemented optical control for spin preparation and manipulation.
- Achieved deterministic spin preparation with up to 96% fidelity.
Main Results:
- Demonstrated an efficient spin-photon interface integrated within a nanophotonic waveguide.
- Successfully implemented a single-spin photonic switch, where the electron spin state controls photon flow.
- Achieved high fidelity (up to 96%) in deterministic spin state preparation.
Conclusions:
- The developed spin-photon interface efficiently links electron spin quantum memory with photonic information carriers.
- This technology is a significant step towards building quantum nodes and networks.
- Potential applications include on-chip photon-photon gates, single-photon transistors, and photonic cluster state generation.
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