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arXiv · 2310.07058

Ion Trap with In-Vacuum High Numerical Aperture Imaging for a Dual-Species Modular Quantum Computer

Allison L. Carter·Jameson O'Reilly·George Toh·Sagnik Saha·Mikhail Shalaev·Isabella Goetting·Christopher Monroe
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Abstract

Photonic interconnects between quantum systems will play a central role in both scalable quantum computing and quantum networking. Entanglement of remote qubits via photons has been demonstrated in many platforms; however, improving the rate of entanglement generation will be instrumental for integrating photonic links into modular quantum computers. We present an ion trap system that has the highest reported free-space photon collection efficiency for quantum networking. We use a pair of in-vacuum aspheric lenses, each with a numerical aperture of 0.8, to couple 10% of the 493 nm photons emitted from a $^{138}$Ba$^+$ ion into single-mode fibers. We also demonstrate that proximal effects of the lenses on the ion position and motion can be mitigated.

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Allison L. Carter, Jameson O'Reilly, George Toh, Sagnik Saha, Mikhail Shalaev, Isabella Goetting, Christopher Monroe. 2023-10-10. Ion Trap with In-Vacuum High Numerical Aperture Imaging for a Dual-Species Modular Quantum Computer. https://doi.org/10.1063/5.0180732

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