Quantum state-controlled directional spontaneous emission of photons into a nanophotonic waveguide

• DOI: 10.1038/ncomms6713
• Publication Date: 2014-12-12T12:51:51Z
• Authors: R. Mitsch; C. Sayrin; B. Albrecht; P. Schneeweiss; A. Rauschenbeutel
• Keywords: Nanophotonics; Waveguide; Quantum imaging; Superradiance; Light emission

Abstract The spin of light in subwavelength-diameter waveguides can be orthogonal to the propagation direction photons because strong transverse confinement. This changes sign when is reversed. Using this effect, we demonstrate directional spontaneous emission by laser-trapped caesium atoms into an optical nanofibre and control their excited state atomic emitters. In particular, tune counter-propagating guided modes from symmetric strongly asymmetric, where more than "Equation missing"<!-- image only, no MathML or LaTex -->% power launched one other direction. We expect our results have important implications for research quantum nanophotonics implementations integrated signal processing regime.