Beyond Antibunching: Photon Correlation Analysis Reveals Blinking Origin

Patricia Kallert; Santiago Bermúdez-Feijóo; Giorgio De Pascalis; Nicolas Claro-Rodriguez; Ioannis Caltzidis; Normen Auler; Eva Berger; Rebecca Aschwanden; Tobias Krieger; Saimon. F. Covre da Silva; Sandra Stroj; Quirin Buchinger; Michele B. Rota; Thomas Hummel; Sven Höfling; Armando Rastelli; Rinaldo Trotta; Dirk Reuter; Sonja Barkhofen; Klaus D. Jöns; Tobias Huber-Loyola

arXiv · 2609.28139

Beyond Antibunching: Photon Correlation Analysis Reveals Blinking Origin

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Abstract

A variety of quantum emitters compete in the quest for the best single-photon source for photonic quantum technologies. Consequently, only a consistent approach to analyze the second-order auto correlation function allows comparison of the multi-photon contribution ($g^{(2)}(0)$) of different sources. However, the community employs different and inconsistent methods for blinking sources, leading to incomparable benchmarks of source quality. Here, we use the emission of an inherently non-blinking quantum dot (QD) and apply artificial blinking through two different mechanisms: masking the recorded raw data in post-processing and emulation of a blinking system by gating the laser excitation pulses. We then compare the $g^{(2)}(0)$ values with the non-blinking result. For the analysis, we investigate five estimators of $g^{(2)}(0)$ actively used in the literature. While fitting the envelope of the correlations on long-time scales with the correct blinking model is the best choice, normalizing to the Poisson level gives by far the worst proximity. Furthermore, we test our predictive model to identify the underlying blinking mechanism of a QD in a circular Bragg grating cavity.

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Patricia Kallert, Santiago Bermúdez-Feijóo, Giorgio De Pascalis, Nicolas Claro-Rodriguez, Ioannis Caltzidis, Normen Auler, Eva Berger, Rebecca Aschwanden, Tobias Krieger, Saimon. F. Covre da Silva, Sandra Stroj, Quirin Buchinger, Michele B. Rota, Thomas Hummel, Sven Höfling, Armando Rastelli, Rinaldo Trotta, Dirk Reuter, Sonja Barkhofen, Klaus D. Jöns, Tobias Huber-Loyola. 2026-09-23. Beyond Antibunching: Photon Correlation Analysis Reveals Blinking Origin. https://arxiv.org/abs/2609.28139

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