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This research introduces HAGEM, a novel broadband quantum memory protocol utilizing chemically engineered Eu$^{3+}$ molecular complexes to achieve 14.9% storage efficiency and 200MHz bandwidth. By leveraging specific hyperfine level correlations through chemical synthesis, the study demonstrates capabilities in rare-earth ion systems that existing solid-state materials cannot match, paving the way for scalable quantum network components. This work establishes a critical framework for material design that bridges molecular engineering with practical quantum optical storage applications.
Broadband Quantum Optical Storage with Chemically Engineered Molecular Eu$^\text{{3+}}$ Complex
arXiv:2609.28271v1 Announce Type: new Abstract: Broadband quantum memory devices are essential elements for future quantum networks. Here we propose a broadband quantum memory scheme called Hole Anti-hole Grating Echo Memory (HAGEM) for rare-earth ions in solids. We provide a Eu$^\text{{3+}}$ molecular complex with special hyperfine level structures of which the hyperfine level separations are in a specific mathematical correlation that can be obtained by harnessing chemical engineering. Using the memory protocol and material, we experimentally demonstrate a quantum optical storage efficiency of 14.9% and a memory bandwidth of 200MHz, which can easily be extended to a few GHz. With this demonstration, we show the first quantum application enabled by molecular engineering which cannot be achieved by any other existing Eu$^\text{3+}$ solid-state materials. In addition, we provide a framework for the chemical engineering of solid-state materials with rare-earth ions for quantum applications consisting of material design, synthesis & characterization techniques, and analytical methods for the quantum properties of rare-earth (RE) ions in solids. This work establishes a new direction in which molecular rare-earth ions can be used for a wide range of quantum applications, which cannot be realized by existing solid-state materials. This will greatly facilitate the development of molecular quantum emitter systems for real world applications.
Abstract:Broadband quantum memory devices are essential elements for future quantum networks. Here we propose a broadband quantum memory scheme called Hole Anti-hole Grating Echo Memory (HAGEM) for rare-earth ions in solids. We provide a Eu$^\text{3+}$ molecular complex with special hyperfine level structures of which the hyperfine level separations are in a specific mathematical correlation that can be obtained by harnessing chemical engineering. Using the memory protocol and material, we experimentally demonstrate a quantum optical storage efficiency of 14.9% and a memory bandwidth of 200MHz, which can easily be extended to a few GHz. With this demonstration, we show the first quantum application enabled by molecular engineering which cannot be achieved by any other existing Eu$^\text{3+}$ solid-state materials. In addition, we provide a framework for the chemical engineering of solid-state materials with rare-earth ions for quantum applications consisting of material design, synthesis & characterization techniques, and analytical methods for the quantum properties of rare-earth (RE) ions in solids. This work establishes a new direction in which molecular rare-earth ions can be used for a wide range of quantum applications, which cannot be realized by existing solid-state materials. This will greatly facilitate the development of molecular quantum emitter systems for real world applications.
Quantum Physics (quant-ph); Chemical Physics (physics.chem-ph)
arXiv:2609.28271 [quant-ph]
(or arXiv:2609.28271v1 [quant-ph] for this version)
https://doi.org/10.48550/arXiv.2609.28271 Focus to learn more arXiv-issued DOI via DataCite (pending registration)
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