Experimental protocol for high-fidelity heralded photon-to-atom quantum state transfer

Area of Science:

• Quantum Information Science
• Quantum Communication Networks
• Atomic Physics

Background:

• Quantum networks leverage quantum phenomena like coherence and entanglement for secure communication and enhanced computation.
• Atom-based quantum memories and processors, linked by photonic channels, are key platforms for building these networks.
• Efficient quantum state conversion between photons and atoms is essential for interconnecting quantum devices.

Purpose of the Study:

• To present an experimental protocol for high-fidelity photon-to-atom quantum state conversion.
• To demonstrate reliable mapping of a photon's polarization state onto an atom's spin state.
• To achieve heralded conversion, confirming successful state transfer via emitted photons.

Main Methods:

• Utilizing controlled absorption of single photons by single atoms.
• Mapping the photon's polarization state to the atom's spin state.
• Employing heralded single-photon emission to confirm successful state transfer.

Main Results:

• Achieved >95% fidelity in mapping photon polarization to atomic spin states.
• Demonstrated heralded conversion, with successful events confirmed by single emitted photons.
• Recorded a high rate of successful state transfer events (>80 s⁻¹).

Conclusions:

• The developed protocol provides a crucial building block for atom-based quantum networks.
• High-fidelity, heralded photon-to-atom conversion is experimentally demonstrated.
• This method ensures reliable transfer of quantum information for further quantum operations.