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arXiv · 2607.11494

A diode nanocavity for fast, efficient and tunable emission of highly entangled photon pairs and Fourier-transform-limited single photons

Ievgen Brytavskyi·Thomas Oberleitner·Christian Weidinger·Maximilian Aigner·Gabriel Undeutsch·Tobias Steindl·Johannes Reindl·Ailton Garcia Jr.·Melina Peter·Christian Schimpf·Santanu Manna·Michele B. Rota·Quirin Buchinger·Sven Höfling·Tobias Huber-Loyola·Rinaldo Trotta·Tobias M. Krieger·Eva Schöll·Armando Rastelli
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Abstract

Deterministic sources of entangled photon pairs and indistinguishable photons are expected to play a key role in photonic quantum technologies. Semiconductor quantum dots are promising candidates due to their on-demand emission and compatibility with nanophotonic structures. However, current implementations face trade-offs between extraction efficiency, Purcell enhancement, as well as charge noise that causes blinking and degrades indistinguishability. Here we demonstrate a tunable nano-optoelectronic device based on a quantum dot embedded in a p-i-n diode circular-Bragg-grating-resonator and featuring extraction efficiencies up to 0.55(6) and Purcell-factor of $\sim$8. The device generates wavelength-tunable entangled photon pairs with suppressed blinking and raw (corrected) concurrence > 0.89 (0.91) over a range of 1.6 nm. The very same source also emits single, nearly Fourier-limited and highly indistinguishable photons with raw (corrected) $\mathcal{V}_{\text{HOM}}$ = 0.951(4) (0.988(6)). These results demonstrate a viable platform for semiconductor quantum photonics.

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Ievgen Brytavskyi, Thomas Oberleitner, Christian Weidinger, Maximilian Aigner, Gabriel Undeutsch, Tobias Steindl, Johannes Reindl, Ailton Garcia Jr., Melina Peter, Christian Schimpf, Santanu Manna, Michele B. Rota, Quirin Buchinger, Sven Höfling, Tobias Huber-Loyola, Rinaldo Trotta, Tobias M. Krieger, Eva Schöll, Armando Rastelli. 2026-07-13. A diode nanocavity for fast, efficient and tunable emission of highly entangled photon pairs and Fourier-transform-limited single photons. https://arxiv.org/abs/2607.11494

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