title: Optical anisotropy in individual porous silicon nanoparticles containing multiple chromophores.
abstract: Polarization anisotropy is investigated in single porous silicon nanoparticles containing multiple chromophores. Two classes of nanoparticles, low current density and high current density, are studied. Low current density samples exhibit red-shifted spectra and contain only one or two chromophores. High current density particles, on average, contain less than four chromophores and display a blue-shifted spectrum. We utilize single-molecule spectroscopy to probe the polarization effects of the particles, and we show that both classes of particles are influenced by a polarized excitation source. These results are exciting at the fundamental level for understanding coupled quantum dot emitters as well as for applications involving single-photon sources or silicon-based polarization-sensitive detectors.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, Santa Barbara, California 93106, USA.
authors.forename: Donald J
authors.initials: DJ
authors.lastname: Sirbuly
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Gargas
authors.forename: Michael D
authors.initials: MD
authors.lastname: Mason
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Carson
authors.forename: Steven K
authors.initials: SK
authors.lastname: Buratto
mesh_terms: D016880:Anisotropy; D003460:Crystallization / Q000379:methods*; D008027:Light; D008163:Luminescent Measurements / Q000379:methods*; D046911:Macromolecular Substances / Q000737:chemistry; D008422:Materials Testing; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D012031:Refractometry; D012542:Scattering, Radiation; D012825:Silicon / Q000737:chemistry*; D013499:Surface Properties; D014025:Titanium / Q000737:chemistry*
chemical_list: D046911:Macromolecular Substances; C009495:titanium dioxide; D014025:Titanium; D012825:Silicon