Alessandro Laneve, Michele B. Rota, Francesco Basso Basset, Mattia Beccaceci, Valerio Villari, Thomas Oberleitner, Yorick Reum, Tobias M. Krieger, Quirin Buchinger, Saimon F. Covre da Silva, Andreas Pfenning, Sandra Stroj, Sven Höfling, Armando Rastelli, Tobias Huber-Loyola, Rinaldo Trotta
{"title":"Wavevector-resolved polarization entanglement from radiative cascades","authors":"Alessandro Laneve, Michele B. Rota, Francesco Basso Basset, Mattia Beccaceci, Valerio Villari, Thomas Oberleitner, Yorick Reum, Tobias M. Krieger, Quirin Buchinger, Saimon F. Covre da Silva, Andreas Pfenning, Sandra Stroj, Sven Höfling, Armando Rastelli, Tobias Huber-Loyola, Rinaldo Trotta","doi":"arxiv-2409.07875","DOIUrl":null,"url":null,"abstract":"The generation of entangled photons from radiative cascades has enabled\nmilestone experiments in quantum information science with several applications\nin photonic quantum technologies. Significant efforts are being devoted to\npushing the performances of near-deterministic entangled-photon sources based\non single quantum emitters often embedded in photonic cavities, so to boost the\nflux of photon pairs. The general postulate is that the emitter generates\nphotons in a nearly maximally entangled state of polarization, ready for\napplication purposes. Here, we demonstrate that this assumption is unjustified.\nWe show that in radiative cascades there exists an interplay between photon\npolarization and emission wavevector, strongly affecting quantum correlations\nwhen emitters are embedded in micro-cavities. We discuss how the polarization\nentanglement of photon pairs from a biexciton-exciton cascade in quantum dots\nstrongly depends on their propagation wavevector, and it can even vanish for\nlarge emission angles. Our experimental results, backed by theoretical\nmodelling, yield a brand-new understanding of cascaded emission for various\nquantum emitters. In addition, our model provides quantitative guidelines for\ndesigning optical microcavities that retain both a high degree of entanglement\nand collection efficiency, moving the community one step further towards an\nideal source of entangled photons for quantum technologies.","PeriodicalId":501226,"journal":{"name":"arXiv - PHYS - Quantum Physics","volume":"8 1","pages":""},"PeriodicalIF":0.0000,"publicationDate":"2024-09-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"arXiv - PHYS - Quantum Physics","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/arxiv-2409.07875","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"","JCRName":"","Score":null,"Total":0}
引用次数: 0
Abstract
The generation of entangled photons from radiative cascades has enabled
milestone experiments in quantum information science with several applications
in photonic quantum technologies. Significant efforts are being devoted to
pushing the performances of near-deterministic entangled-photon sources based
on single quantum emitters often embedded in photonic cavities, so to boost the
flux of photon pairs. The general postulate is that the emitter generates
photons in a nearly maximally entangled state of polarization, ready for
application purposes. Here, we demonstrate that this assumption is unjustified.
We show that in radiative cascades there exists an interplay between photon
polarization and emission wavevector, strongly affecting quantum correlations
when emitters are embedded in micro-cavities. We discuss how the polarization
entanglement of photon pairs from a biexciton-exciton cascade in quantum dots
strongly depends on their propagation wavevector, and it can even vanish for
large emission angles. Our experimental results, backed by theoretical
modelling, yield a brand-new understanding of cascaded emission for various
quantum emitters. In addition, our model provides quantitative guidelines for
designing optical microcavities that retain both a high degree of entanglement
and collection efficiency, moving the community one step further towards an
ideal source of entangled photons for quantum technologies.