Asymmetric two-photon response of an incoherently driven quantum emitter
- Author(s)
- Lennart Jehle, Lena M. Hansen, Patrik I. Sund, Thomas W. Sandø, Raphael Joos, Michael Jetter, Simone L. Portalupi, Mathieu Bozzio, Peter Michler, Philip Walther
- Abstract
Quantum emitters promise to emit exactly one photon when pumped by a laser pulse. However, even in ideal systems, re-excitation during the laser pulse duration causes the consecutive emission of two photons, thus limiting the single-photon purity. Although the probability and characteristics of re-excitation are largely determined by the excitation scheme, until now, only resonant driving has been studied. Here, we demonstrate qualitative differences for phonon-assisted excitation and resolve the distinct temporal and spectral profile of each of the photons. These uncover correlations between the emission time and wavelength, resulting in an asymmetric two-photon spectrum. On a fundamental level, we show that this spectrum provides direct access to the Rabi frequency of an incoherently driven quantum dot. On the application side, we leverage the asymmetry to selectively suppress multiphoton noise, ensuring high single-photon purity regardless of the laser pulse length and thus enhancing implementations across quantum cryptography and quantum computing.
- Organisation(s)
- Quantum Science
- External organisation(s)
- Universität Stuttgart, Österreichische Akademie der Wissenschaften (ÖAW)
- Journal
- Nature Communications
- Volume
- 17
- No. of pages
- 8
- ISSN
- 2041-1723
- DOI
- https://doi.org/10.48550/arXiv.2507.07082
- Publication date
- 07-2026
- Peer reviewed
- Yes
- Austrian Fields of Science 2012
- 103026 Quantum optics
- ASJC Scopus subject areas
- General Chemistry, General Biochemistry,Genetics and Molecular Biology, General, General Physics and Astronomy
- Portal url
- https://ucrisportal.univie.ac.at/en/publications/8d23b6cb-83ee-49e5-86f0-6bac16bf2dee