Picosecond Lifetimes with High Quantum Yields from Single-Photon-Emitting Colloidal Nanostructures at Room...

Area of Science:

• Nanophotonics
• Quantum Optics
• Biomolecular Engineering

Background:

• Optimizing solid-state light sources requires minimizing luminescence lifetime and maximizing quantum yield.
• Nonradiative processes significantly impact performance at room temperature.
• Fluorescent molecules coupled with plasmonic nanostructures offer enhanced optical properties.

Purpose of the Study:

• To demonstrate DNA-templated gold nanoparticle dimers as efficient single-photon emitters.
• To achieve ultrashort luminescence lifetimes and high quantum yields in nanostructure-based light sources.
• To enable parallel production of millions of bright fluorescent nanostructures.

Main Methods:

• Fabrication of 60 and 80 nm gold nanoparticle dimers templated by DNA.
• Incorporation of single fluorescent molecules within the nanoparticle dimers.
• Characterization using fluorescence spectroscopy on fixed and diffusing nanostructures.
• Quantitative estimation of decay rate and fluorescence intensity distributions.

Main Results:

• Achieved single-photon emission with luminescence lifetimes below 10 picoseconds (ps).
• Observed typical quantum yields in the range of 45-70%.
• Demonstrated excellent agreement between experimental data and theoretical calculations.
• Showcased parallel production of millions of bright nanostructures with radiative lifetimes under 100 ps.

Conclusions:

• DNA-templated gold nanoparticle dimers are effective for creating efficient single-photon emitters.
• Ultrashort luminescence lifetimes and high quantum yields are achievable, surpassing limitations of nonradiative decay.
• The developed method allows for scalable, parallel synthesis of advanced fluorescent nanostructures for light-source applications.