Enhanced photoluminescence from plasmonic apparatus with two resonant cavity wavelengths

A method comprising:

• directing a first electromagnetic beam having a first wavelength λ1 at a plasmonic apparatus;
• and
• emitting a second electromagnetic beam having at a second wavelength λ2 from the plasmonic apparatus, the second electromagnetic beam having a lower quantum energy level than the first electromagnetic beam,
• the plasmonic apparatus comprising:
• a substrate having a first negative-permittivity layer comprising a first plasmonic surface;
• a plasmonic nanoparticle having a base with a second negative-permittivity layer comprising a second plasmonic surface;
• a dielectric-filled gap between the first plasmonic surface and the second plasmonic surface;
• and
• a plasmonic cavity created by an assembly of the first plasmonic surface, the second plasmonic surface, and the dielectric-filled gap, and having a spectrally separated first fundamental resonant cavity wavelength λ1 and second fundamental resonant cavity wavelength λ2.

A plasmonic nanoparticle dimer comprising:

• a first plasmonic nanoparticle having a base with a first negative-permittivity layer comprising a first plasmonic surface;
• a second plasmonic nanoparticle having a base with a second negative-permittivity layer comprising a second plasmonic surface;
• dielectric-filled gap between the first plasmonic outer surface and the second plasmonic outer surface, a dielectric material of the dielectric-filed gap including a non-linear optical dielectric material;
• a plasmonic cavity created by an assembly of the first plasmonic surface, the second plasmonic surface, and the dielectric-filled gap, and having a spectrally separated first fundamental resonant cavity wavelength λ1 and second fundamental resonant cavity wavelength λ2.

A method comprising:

• applying an electromagnetic excitation at a first fundamental resonant cavity wavelength λ1 to a plurality of plasmonic nanoparticle dimers;
• and
• receiving from the plurality of plasmonic nanoparticle dimers electromagnetic waves emitted at a second fundamental resonant cavity wavelength λ2,
• each plasmonic nanoparticle dimer of the plurality of plasmonic nanoparticle dimers comprising;
• a first plasmonic nanoparticle having a base with a first negative-permittivity layer comprising a first plasmonic surface;
• and
• a second plasmonic nanoparticle having a base with a second negative-permittivity layer comprising a second plasmonic surface;
• and
• a dielectric-filled gap between the first plasmonic outer surface and the second plasmonic outer surface;
• a plasmonic cavity created by an assembly of the first plasmonic surface, the second plasmonic surface, and the dielectric-filled gap, and having a spectrally separated first fundamental resonant cavity wavelength λ1 and second fundamental resonant cavity wavelength λ2.