Скачать или смотреть Towards quantum memory

We describe the successful demonstration of a highly efficient quantum memory essential for advancing repeater-based quantum communication and large-scale quantum computation. Historically, attempts to store true single-photon qubits suffered from efficiencies far below the necessary 50% threshold required for practical applications. The researchers solved this problem by designing a specialized quantum memory that employs balanced two-channel electromagnetically induced transparency (EIT) within an ensemble of laser-cooled rubidium atoms. By optimizing the single-photon temporal waveforms and using angled control beams to suppress noise, they significantly improved performance. Their results show a remarkable single-photon polarization qubit memory efficiency greater than 85% with a fidelity exceeding 99%. This breakthrough marks the first time a flying single-photon qubit memory has surpassed the crucial efficiency benchmark, pushing the technology closer to practical quantum information processing.