Tuning Spontaneous Emission through Waveguide Cavity Effects in Semiconductor Nanowires

Area of Science:

• Nanophotonics
• Quantum Optics
• Materials Science

Background:

• Tailoring waveguide cavities and quantum emitters is crucial for nanophotonics.
• Pushing into the deep subwavelength regime increases nonradiative losses due to surface defects.

Purpose of the Study:

• To demonstrate efficient suppression of nonradiative recombination in thin waveguide cavities.
• To explore the use of core-shell semiconductor nanowires for enhanced nanophotonic devices.
• To investigate the control of mobile emitters within one-dimensional waveguides.

Main Methods:

• Utilizing core-shell semiconductor nanowires as 1D waveguides.
• Experimentally controlling nanowire diameter to tune exciton luminescence lifetime.
• Engineering the dielectric environment to manipulate luminescence lifetime.
• Demonstrating spatial control of mobile emitters along the nanowire axis.

Main Results:

• Achieved efficient suppression of nonradiative recombination in thin waveguide cavities.
• Demonstrated tunable luminescence lifetime of free excitons across two orders of magnitude (up to 80 ns) by controlling nanowire diameter.
• Showed that luminescence lifetime can be engineered by modifying the dielectric environment.
• Exhibited all-dielectric spatial control of mobile emitters along the 1D nanowire waveguide.

Conclusions:

• Core-shell semiconductor nanowires offer a promising platform for overcoming nonradiative losses in subwavelength nanophotonics.
• The ability to control exciton dynamics and spatial distribution in 1D waveguides opens possibilities for active, tunable nanophotonic devices.
• This approach facilitates the development of novel quantum emitters and light-matter interaction schemes.