Recently, the concept of integrating photonics and electronics, with the goal of producing faster electronics and more effective solar cells, has been attracting a significant amount of interest. To properly understand this idea, the small-scale electronic and photovoltaic processes must be investigated on the atomic or molecular level.

Prof. Hrvoje Petek and his research group at the University of Pittsburgh are aiming to do just that, operating under the notion that processes cannot be controlled until they are adequately measured. To perform their investigations, the research group used a two-photon photoemission spectroscopy method, enabled by IMPULSE laser and NOPA from Clark-MXR.

The researchers specifically examined processes occurring at the interface of silver nanoparticles and TiO2, where a combination of optical, electronic and chemical properties are all taking place. The metal nanoparticles were efficient at absorbing light, due to Plasmon resonance, which concentrated energy before transferring to a semiconductor substrate. Some details of the exact mechanism remain unexplored, but the group’s recent publication “Plasmonic coupling at a metal/semiconductor interface” examines the energy transfer mechanism in this metal/semiconductor heterojunction to understand the relationship between light and electronics.

For further in-depth reading, please see the full publication: Plasmonic coupling at a metal/semiconductor interface, Shijing Tan, Adam Argondizzo, Jindong Ren, Liming Liu, Jin Zhao and Hrvoje Petek, Nature Photonics,