Mr Lorenzo Carosini

Multiphoton experiments with semiconductor quantum-dot sources

Over the past two decades, semiconductor quantum dots have emerged as a leading platform for realizing highly efficient sources of near-identical single-photon. At the Christian Doppler Laboratory at the University of Vienna, we leverage commercially available quantum dots (from Quandela and Sparrow) to push the boundaries of photonic quantum information processing and explore fundamental quantum optics phenomena. In this talk, I will present the latest breakthroughs from our laboratory, with a particular focus on applications in photonic quantum computing. Highlights include the development of a resource-efficient programmable time-bin processor for multi-photon interference [1], the heralded generation of three-photon GHZ states [2], and the pioneering experimental demonstration of single-photon indistinguishability purification using a linear optical circuit [3]. References: [1] L. Carosini et al. , "Programmable multiphoton quantum interference in a single spatial mode", Sci. Adv.10, eadj0993(2024) [2] H. Cao et al., "Photonic source of heralded Greenberger-Horne-Zeilinger states", Phys. Rev. Lett. 132, 130604 (2024). [3] C.F.D. Faurby et al., “Purifying photon indistinguishability through quantum interference” (2024). arXiv:2403.12866