The ultimate control of light-matter interaction is achieved when a single emitter strongly interacts with a single photon. A manipulation at the level of single quanta is not only of fundamental interest but is of special importance for emerging quantum technologies, such as quantum information processing. In this talk I will first briefly review our experimental progress on the interaction of strongly focused photons with a single molecule [1, 2]. Then I will discuss how optical antennas can be used to enhance light-emitter interaction and how the emission properties of a single emitter can be dramatically altered. Two types of antennas are presented. With a metallic nanoantenna, we experimentally achieved a two orders of magnitude enhancement of the radiative decay rate of a single colloidal quantum dot [3]. In another experiment we embedded a single emitter in a planar dielectric antenna, which directs the emission towards the collection optics. We realized a single-photon source with a collection efficiency of 99% [4]. The result is the most regular stream of single photons reported to date, where the measured intensity fluctuations were limited by our detection efficiency and amounted to 2.2 dB squeezing [5].

References
[1] A. Maser et al., Nature Photonics 10, 450-453 (2016).
[2] D. Wang et al., Phys. Rev. X 7, 021014 (2017).
[3] K. Matsuzaki et al., Scientific Reports 7, 42307 (2017).
[4] X.-L. Chu et al., Optica 1, 203 (2014).
[5] X.-L. Chu et al., Nature Photonics 11, 58–62, (2017).

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Bio

Stephan Götzinger is a professor at the Friedrich-Alexander University of Erlangen-Nürnberg and the Max Planck Institute for the Science of Light. He received a PhD degree in Physics from the Humboldt-University of Berlin and his habilitation from ETH Zurich, where he held a privatdozent position in the Department of Chemistry and Applied Biosciences until 2015. His research focuses on solid-state quantum optics.