title: Single quantum dot controls a plasmonic cavity's scattering and anisotropy.
abstract: Plasmonic cavities represent a promising platform for controlling light-matter interaction due to their exceptionally small mode volume and high density of photonic states. Using plasmonic cavities for enhancing light's coupling to individual two-level systems, such as single semiconductor quantum dots (QD), is particularly desirable for exploring cavity quantum electrodynamic (QED) effects and using them in quantum information applications. The lack of experimental progress in this area is in part due to the difficulty of precisely placing a QD within nanometers of the plasmonic cavity. Here, we study the simplest plasmonic cavity in the form of a spherical metallic nanoparticle (MNP). By controllably positioning a semiconductor QD in the close proximity of the MNP cavity via atomic force microscope (AFM) manipulation, the scattering spectrum of the MNP is dramatically modified due to Fano interference between the classical plasmonic resonance of the MNP and the quantized exciton resonance in the QD. Moreover, our experiment demonstrates that a single two-level system can render a spherical MNP strongly anisotropic. These findings represent an important step toward realizing quantum plasmonic devices.
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712; Center for Complex Quantum Systems, The University of Texas at Austin, Austin, TX 78712;
authors.forename: Thomas
authors.initials: T
authors.lastname: Hartsfield
authors.affiliation: Department of Chemistry, Rice University, Houston, TX 77005;
authors.forename: Wei-Shun
authors.initials: WS
authors.lastname: Chang
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712; Center for Complex Quantum Systems, The University of Texas at Austin, Austin, TX 78712;
authors.forename: Seung-Cheol
authors.initials: SC
authors.lastname: Yang
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712; Center for Complex Quantum Systems, The University of Texas at Austin, Austin, TX 78712;
authors.forename: Tzuhsuan
authors.initials: T
authors.lastname: Ma
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712; Center for Complex Quantum Systems, The University of Texas at Austin, Austin, TX 78712; Department of Physics and Applied Optics, Beijing Area Major Laboratory, Beijing Normal University, Beijing 100875, China;
authors.forename: Jinwei
authors.initials: J
authors.lastname: Shi
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712; Center for Complex Quantum Systems, The University of Texas at Austin, Austin, TX 78712;
authors.forename: Liuyang
authors.initials: L
authors.lastname: Sun
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712; Center for Complex Quantum Systems, The University of Texas at Austin, Austin, TX 78712; Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712; gena@physics.utexas.edu slink@rice.edu elaineli@physics.utexas.edu.
authors.forename: Gennady
authors.initials: G
authors.lastname: Shvets
authors.affiliation: Department of Chemistry, Rice University, Houston, TX 77005; Department of Electrical and Computer Engineering, Rice University, Houston, TX 77005 gena@physics.utexas.edu slink@rice.edu elaineli@physics.utexas.edu.
authors.forename: Stephan
authors.initials: S
authors.lastname: Link
authors.affiliation: Department of Physics, The University of Texas at Austin, Austin, TX 78712; Center for Complex Quantum Systems, The University of Texas at Austin, Austin, TX 78712; Texas Materials Institute, The University of Texas at Austin, Austin, TX 78712; gena@physics.utexas.edu slink@rice.edu elaineli@physics.utexas.edu.
authors.forename: Xiaoqin
authors.initials: X
authors.lastname: Li
keywords: Fano resonance; hybrid nanostructures; optical spectroscopy; plasmonic cavities; quantum systems