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arXiv · 2210.05530

Variance-Based Sensitivity Analysis of $\Lambda$-type Quantum Memory

Kai Shinbrough·Virginia O. Lorenz
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Abstract

The storage and retrieval of photonic quantum states, quantum memory, is a key resource for a wide range of quantum applications. Here we investigate the sensitivity of $\Lambda$-type quantum memory to experimental fluctuations and drift. We use a variance-based approach, focusing on the effects of fluctuations and drift on memory efficiency. We consider shot-to-shot fluctuations of the memory parameters, and separately we consider longer timescale drift of the control field parameters. We find the parameters that a quantum memory is most sensitive to depend on the quantum memory protocol being employed, where the observed sensitivity agrees with physical interpretation of the protocols. We also present a general framework that is applicable to other figures of merit beyond memory efficiency. These results have practical ramifications for quantum memory experiments.

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Kai Shinbrough, Virginia O. Lorenz. 2022-10-11. Variance-Based Sensitivity Analysis of $\Lambda$-type Quantum Memory. https://doi.org/10.1103/physreva.107.033703

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