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arXiv · 2409.12503

Progress towards efficient 4-level photon echo memories

James Stuart·Kieran Smith·Morgan Hedges·Rose Ahlefeldt·Matthew Sellars
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Abstract

Quantum memories could benefit many devices in quantum information processing. For a quantum to be useful in real-world applications, the quantum memory must have a high recall efficiency. Here we demonstrate an efficient (up to 80%) spin-storage quantum memory in Er:YSO, using the 4-level rephased amplified spontaneous emission protocol. We show non-classical correlations between the ASE and RASE fields produced by the quantum memory. Also, we demonstrate the storage of 70 temporal modes, with a write time of 150 us, and a storage time of 25 us. Finally, a clear pathway is presented to improve the efficiency, storage time, and mode capacity. Such a device would have applications in quantum networking and measurement-based quantum computing.

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James Stuart, Kieran Smith, Morgan Hedges, Rose Ahlefeldt, Matthew Sellars. 2024-09-19. Progress towards efficient 4-level photon echo memories. https://arxiv.org/abs/2409.12503

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