Soellner, Immo Mahmoodian, Sahand Hansen, Sofie Lindskov Midolo, Leonardo Javadi, Alisa Kirsanske, Gabija Pregnolato, Tommaso El-Ella, Haitham Lee, Eun Hye Song, Jin Dong Stobbe, Soren Lodahl, Peter 2024-01-20T06:04:35Z 2024-01-20T06:04:35Z 2021-09-05 2015-09 1748-3387 https://pubs.kist.re.kr/handle/201004/125055 Engineering photon emission and scattering is central to modern photonics applications ranging from light harvesting to quantum-information processing. To this end, nanophotonic waveguides are well suited as they confine photons to a one-dimensional geometry and thereby increase the light-matter interaction. In a regular waveguide, a quantum emitter interacts equally with photons in either of the two propagation directions. This symmetry is violated in nanophotonic structures in which non-transversal local electric-field components imply that photon emission(1,2) and scattering(3) may become directional. Here we show that the helicity of the optical transition of a quantum emitter determines the direction of single-photon emission in a specially engineered photonic-crystal waveguide. We observe single-photon emission into the waveguide with a directionality that exceeds 90% under conditions in which practically all the emitted photons are coupled to the waveguide. The chiral light-matter interaction enables deterministic and highly directional photon emission for experimentally achievable on-chip non-reciprocal photonic elements. These may serve as key building blocks for single-photon optical diodes, transistors(4) and deterministic quantum gates(5). Furthermore, chiral photonic circuits allow the dissipative preparation of entangled states of multiple emitters(6) for experimentally achievable parameters(7), may lead to novel topological photon states(8,9) and could be applied for directional steering of light(10-13). English NATURE PUBLISHING GROUP Deterministic photon-emitter coupling in chiral photonic circuits Article 10.1038/NNANO.2015.159 1 NATURE NANOTECHNOLOGY, v.10, no.9, pp.775 - + NATURE NANOTECHNOLOGY 10 9 775 + scie scopus 000360932000013 2-s2.0-84941188307 Nanoscience & Nanotechnology Materials Science, Multidisciplinary Science & Technology - Other Topics Materials Science Article photon?emitter chiral photonic circuits