When multiple metallic nanoparticles are placed close to each other, the plasmons that each of them generates interact with each other, thus modifying the general properties of the system.
If the system is made up of a periodic network of identical nanostructures and configured under the right conditions, these systems are capable of supporting collective behaviors known as network resonances that produce electromagnetic responses much stronger than the sum of the individual plasmons. Such behavior makes these systems an ideal platform to develop new biosensors, light-emitting devices, and color filters, among other applications.

In this work the team has investigated the use of the unique properties of lattice resonances excited by spatially finite light beams to enhance and manipulate heat generation in localized regions.
Through extensive theoretical analysis based on a coupled dipole model, they have shown that arrays that support a lattice resonance absorb more energy per nanoparticle and therefore achieve a much higher temperature rise if illuminated with a laser. pressed than those that do not support this mode.
On the contrary, for continuous wave lighting conditions, the temperature rise is practically independent of the grid period.

In addition, the team has succeeded in designing matrices with two different nanoparticles per unit cell, so that the lattice resonance phenomenon occurs for two different wavelengths, making it possible to independently excite the lattice formed by one type or another of nanoparticles.
The results of this work pave the way for the development of thermoplasmonic applications that exploit the exceptional optical response and design flexibility provided by lattice resonances.