24 March

Broadband Optical Switching of Gaussian Beams Inspired by Bound States in the Continuum (BIC)

Friday 24 March 2023, 10:00am

ICN2 Seminar Room, Campus UAB

By Prof. Patrick Görrn, Large Area Optoelectronics (LGOE) at the University of Wuppertal, Germany.

Abstract:The diffraction of light allows to change its direction. Therefore, tuning the diffraction efficiency enables control of the pathway of light within optical systems. However, for this approach to be useful, the diffraction efficiency must be tuneable close to zero. In this context, loss-free dielectric BICs are promising as their diffraction can be tuned with small permittivity changes. However, due to their singular nature in both energy and momentum, fast and local optical switching based on BICs remains challenging. Here, different approaches are introduced to meet this challenge. Firstly, hybrid photonic–plasmonic BICs are introduced that exhibit an increased performance compared to purely dielectric ones. In the second step quasi-bound node modes are introduced. Finally, a broadband phenomenon inspired by BICs is demonstrated. It allows to switch the direction of a symmetric pair of Gaussian beams. It is demonstrated how this phenomenon can be used to electrically control trapping and detrapping of light from a nonlinear optical waveguide.

CV: Patrick Görrn is a professor of Large Area Optoelectronics (LGOE) at the University of Wuppertal. He holds a diploma (2004) and a PhD degree (2008) in electrical engineering from the University of Braunschweig. After his postdoc as Humboldt fellow at Princeton University (2009 - 2010), he became an assistant professor and Emmy Noether Research Group leader at the University of Wuppertal in 2011. In 2014, he then became a full professor. He received an ERC Starting Grant for his project on solar concentrators in 2015. His research interests include stretchable and flexible optoelectronics, in particular thin film lasers and sensors, laser displays and scanners, and light concentrators.

Hosted by Prof. Clivia M. Sotomayor Torres, Phononic and Photonic Nanostructures Group Leader at ICN2.