---
abstract: 'Efficient sources of many-partite non-classical states are key for the advancement of quantum technologies and for the fundamental testing of quantum mechanics. We demonstrate the generation of time-correlated photon triplets at telecom wavelengths via pulsed cascaded parametric down-conversion in a monolithically integrated source. By detecting the generated states with success probabilities of $(6.25\pm1.09)\times10^{-11}$ per pump pulse at injected powers as low as $10\;\mu\mathrm{W}$, we benchmark the efficiency of the complete system and deduce its high potential for scalability. Our source is unprecedentedly long-term stable, it overcomes interface losses intrinsically due to its monolithic architecture, and the photon-triplet states dominate uncorrelated noise significantly. These results mark crucial progress towards the proliferation of robust, scalable, synchronized and miniaturized quantum technology.'
address: |
    $^1$Applied Physics, University of Paderborn, Warburger Strasse 100, 33098 Paderborn, Germany\
    $^2$stephan.krapick@gmail.com\
    $^3$christine.silberhorn@uni-paderborn.de
author:
- 'Stephan Krapick,$^{1,2}$ Benjamin Brecht,$^{1}$ Harald Herrmann,$^{1}$ Viktor Quiring,$^{1}$ and Christine Silberhorn$^{1,3}$'
title: 'On-chip generation of photon-triplet states'
---

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