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arXiv · 2303.00017

Detection of single ions in a nanoparticle coupled to a fiber cavity

Chetan Deshmukh·Eduardo Beattie·Bernardo Casabone·Samuele Grandi·Diana Serrano·Alban Ferrier·Philippe Goldner·David Hunger·Hugues de Riedmatten
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Abstract

Many quantum information protocols require the storage and manipulation of information over long times, and its exchange between nodes of a quantum network across long distances. Implementing these protocols requires an advanced quantum hardware, featuring, for example, a register of long-lived and interacting qubits with an efficient optical interface in the telecommunication band. Here we present the Purcell-enhanced detection of single solid-state ions in erbium-doped nanoparticles placed in a fiber cavity, emitting photons at 1536 nm. The open-access design of the cavity allows for complete tunability both in space and frequency, selecting individual particles and ions. The ions are confined in a volume two orders of magnitude smaller than in previous realizations, increasing the probability of finding ions separated only by a few nanometers which could then interact. We report the detection of individual spectral features presenting saturation of the emission count rate and linewidth, as expected for two-level systems. We also report an uncorrected $g^{(2)} \left ( 0 \right )$ of 0.24(5) for the emitted field, confirming the presence of a single emitter. Our fully fiber-integrated system is an important step towards the realization of the initially envisioned quantum hardware.

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Chetan Deshmukh, Eduardo Beattie, Bernardo Casabone, Samuele Grandi, Diana Serrano, Alban Ferrier, Philippe Goldner, David Hunger, Hugues de Riedmatten. 2023-02-28. Detection of single ions in a nanoparticle coupled to a fiber cavity. https://doi.org/10.1364/optica.491692

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