Universitat Politècnica de Catalunya

07/10/2017 | Press release | Distributed by Public on 07/21/2017 02:28

Scientists from the UPC investigate reconfigurable and programmable metamaterials

The main drawback that metamaterials currently have is that their design is very specific and static
. They can only be applied to the problem for which they were designed, and their behaviour cannot be reused or changed. The aim from now on must be to overcome these limitations and to design reconfigurable and programmable metamaterials whose behaviour can be changed over time in a controlled manner, thus making them reusable and suited to many more applications, some of which are yet to be discovered.

One of the project's challenges is therefore to be able to easily program the materials' functions. To this end, scientists are working on creating a layer of software that allows the desired function to be easily defined. This layer is responsible for translating functionality into specific operations, which are distributed through the network installed within the metamaterial until they reach the nanoprocessors, which eventually modify the internal structure of the metamaterial to achieve the desired behaviour. This will favour the use of reconfigurable metamaterials and encourage research into new and disruptive uses of this technology. These systems can even become 'invisible' objects if certain conditions are met, such as covering them to prevent electromagnetic waves bouncing off them.

To make all of this possible, a network of sensors and nanoprocessors is necessary inside the metamaterial to allow its properties to be controlled at a very fine resolution: 1 cm for Wi-Fi waves 50 nanometres for light. In the future, these achievements may open the door to the reconfigurable manipulation of light.

The research group NaNoNetworking Center in Catalonia (N3Cat) led by Sergi Abadal, Eduard Alarcón and Albert Cabellos studies what these networks might be like, which is the only way to change the metamaterial's behaviour. They design the network that connects the nanoprocessors that modify the metamaterial's behaviour. Their study covers many aspects of telecommunications engineering and network design in a new environment that has never been analysed until now. Whether a metamaterial can be truly reconfigurable depends on the study's success.

In addition to numerous electronic and medical applications, the new metamaterials will be of great interest in the field of the seismology to modify the waves of an earthquake when they come into contact with buildings, preventing the vibrations and aftershocks that can make them collapse. They will also be of use in the renewable energies sector to improve photovoltaic panels so that they absorb the maximum amount of solar radiation, and will be useful in optics as filters and in sound to improve the installation of sound systems.

The diagram shows how the function of a nanomaterial can be modified from an external device (in this case, a tablet), thanks to the orders received by the built-in drivers in the metamaterial. In the example, the nanomaterial performed the function of absorbing green and is modified to absorb red instead of green.