Magnetic plasmonic nanoparticle positioned on a magnetic plasmonic substrate

An apparatus comprising:

• a magnetic substrate at least partially covered by a first negative-permittivity layer comprising a first plasmonic outer surface;
• a plurality of plasmonic nanoparticles, each plasmonic nanoparticle having a respective magnetic element at least partially covered by a second negative-permittivity layer comprising a second plasmonic outer surface;
• a respective dielectric-filled gap between the first plasmonic outer surface and the second plasmonic outer surface of each plasmonic nanoparticle of the plurality of plasmonic nanoparticles;
• wherein the first plasmonic outer surface, the dielectric-filled gap, and the respective second plasmonic outer surfaces are configured to support bonding surface plasmons, and
• wherein each plasmonic nanoparticle of the plurality of plasmonic nanoparticles is respectively retained on the first plasmonic outer surface by a magnetic attraction between the magnetic substrate and the magnetic element of the plasmonic nanoparticle.

An apparatus comprising:

• a plasmonic nanoparticle dimer including;
• a first plasmonic nanoparticle having a first magnetic element at least partially covered by a first negative-permittivity layer comprising a first plasmonic outer surface;
• and
• a second plasmonic nanoparticle having a second magnetic element at least partially covered by a second negative-permittivity layer comprising a second plasmonic outer surface;
• and
• a separation control structure disposed between the first plasmonic outer surface and the second plasmonic outer surface and configured to maintain a dielectric-filled gap between the first plasmonic outer surface and the second plasmonic outer surface,
• wherein a magnetic attraction between the first magnetic element and the second magnetic element binds the first plasmonic nanoparticle and the second plasmonic nanoparticle together, separated by the dielectric-filled gap maintained by the separation control structure, and
• wherein the first plasmonic outer surface, the dielectric-filled gap, and the second plasmonic outer surface are configured to cooperatively support bonding surface plasmons.

A method comprising:

• applying a layer of dielectric material to at least a portion of a first plasmonic outer surface of each plasmonic nanoparticle of a plurality of first plasmonic nanoparticles, each plasmonic nanoparticle of the plurality of first plasmonic nanoparticles having a first magnetic element at least partially covered by a first negative-permittivity layer comprising a first plasmonic outer surface;
• placing a plurality of second plasmonic nanoparticles proximate to the plurality of first plasmonic nanoparticles, each plasmonic nanoparticle of the plurality of second plasmonic nanoparticles having a second magnetic element at least partially covered by a second negative-permittivity layer comprising a second plasmonic outer surface;
• and
• forming a plurality of plasmonic nanoparticle dimers, each plasmonic nanoparticle dimer of the plurality of plasmonic nanoparticle dimers respectively comprising a plasmonic nanoparticle of the plurality of first plasmonic nanoparticles magnetically bound to a plasmonic nanoparticle of the plurality of second plasmonic nanoparticles, with a dielectric-filled gap maintained by the applied layer of dielectric material between the first plasmonic outer surface of the first bound plasmonic nanoparticle and the second plasmonic outer surface of the second bound plasmonic nanoparticle.