The key concept is to allow IR light to be absorbed at nanostructured metal cathodes to launch surface plasmons (rapid oscillations of electronic charge analogous to sound waves in liquids) to generate a photocurrent. 

The project's strategy uses inverted silicon nano-pyramid arrays covered with thin gold films, manufactured employing low-cost and scalable methods. After optimising the infrared absorption performance, the project objective is now to improve photocurrent delivery with promising results. 

Luis A. Pérez et al. have now written an article at the Project Repository Journal, in which they explain the main goals and results of the project, and the further developments in this area.

The article includes a short video in which the plasmon excitation process by the absorption of NIR light is visualized. The hot spot regions, represented by the bright reddish areas, are the regions where the intensity of the incident NIR light can be amplified up to ten thousand times. These are the perfect spots to inject the electrons from the metal (gold) into the semiconductor (silicon) to generate the photocurrent, that will be collected at a counter electrode.

"We are very happy with this article, which contains a video with some simulation results on how plasmons increase the electromagnetic field at the metal-semiconductor interface (Au-Si, in this case), especially at the hot spots" says Alejandro Goñi, PI of the project.

PLASMIONICO started on September 2019 and will finish on 31 August 2021. 

You can read the article, aimed at general public, in the Project Repository Journal here. 

More information:

• PLASMIONICO at the NANOPTO group website
• PLASMIONICO at the CORDIS website
• The ICMAB welcomes you to the EU Sustainable Energy Week #EUSEW2020
• Announcement of the PostDoc Talk: "Plasmon-enhanced light–matter interaction: from molecular detection to energy harvesting applications" by Luis A. Pérez (Mon, 30 Nov 2020)
• Video of the Postdoc Talk "Plasmon-enhanced light–matter interaction: from molecular detection to energy harvesting applications" by Luis A. Pérez (Mon, 30 Nov 2020)