Article

Subdiffraction photon guidance by quantum-dot cascades

Department of Physics, University of Washington Seattle, Seattle, Washington, United States
Nano Letters (Impact Factor: 12.94). 12/2006; 6(11):2549-53. DOI: 10.1021/nl061958g
Source: PubMed

ABSTRACT We report on a waveguide composed of a cascade of gain-enabled quantum dots with subwavelength dimensions. Fabrication is demonstrated through DNA-mediated self-assembly and a two-layer molecular self-assembly process that enables rapid prototyping. The device, which is identified with fluorescence microscopy and tested by optical near field detection, allows optical signal transfer at a well-defined wavelength in flexible routing geometry, such as straight paths and 90 degrees bends. The structure serves as a critical building block for nanophotonic systems with high integration density.

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