The seminar will take place at the Sala d'Actes Carles Miravitlles and online.

DNA-mediated self-assembly of optical antennas for single-photon emitters

by Guillermo Pedro Acuna, Photonic Nanosystems Group, Department of Physics, University of Fribourg, Switzerland

Friday, 4 March 2022, 12 pm
ICMAB-Sala d'Actes Carles Miravitlles and Online by Zoom. Register here to attend.

Abstract:

Over the last decade, the DNA origami technique¹ has consolidated into the state-of-the-art approach for the self-assembly of nanophotonic² structures since it provides unique control and versatility to organize different molecules and nanoparticles in well-defined geometric arrangements. In particular, this technique has proven extremely useful to fabricate nanophotonic devices with specific functionality by setting single-photon emitters, such as fluorescent molecules or quantum dots, and metallic nanoparticles in precise geometries with high positional and stoichiometric control.

In this contribution, we will first introduce this technique and discuss its strengths and limitations together with a comparison with state-of-the-art top down approaches. Then we will show how this technique can be applied to study light-matter interaction at the single molecule level for enhanced spectroscopies³ and sensing with portable devices such as smartphones⁴. We will also show how these antennas can be engineered to manipulate the fluorescence emission⁵, including directivity and shifting the apparent fluorescence emission center⁶.

Bio:

Since 2018 Guillermo Pedro Acuna is a Full Professor at the Physics department of the University of Fribourg where he leads the Photonic Nanosystems group. He has pioneered the use of the DNA origami technique for nanophotonics focusing on the fabrication of optical antennas for enhanced spectroscopies.

Prof. Acuna obtained his Physics diploma at the Universidad de Buenos Aires (2005) and his PhD degree at the LMU München (2010) under the supervision of Prof. Roland Kersting. He has done a Post-Doc at Prof. Hermann Gaub´s chair for Bio-physics at the LMU München (2010).

From 2011 till 2017 he was group leader at Prof. Philip Tinnefeld´s chair at the Technical University of Braunschweig. In 2018, Prof. Acuna obtained a Full Professor (W3) position at the University of Rostock. His main interests are nanophotonics, plasmonics, DNA nanotechnology, nanoscopy, single molecule techniques and sensing.

References:

1. Rothemund, P. W. K. Folding DNA to create nanoscale shapes and patterns. Nature 440, 297–302 (2006).
2. Kuzyk, A., Jungmann, R., Acuna, G. P. & Liu, N. DNA Origami Route for Nanophotonics. ACS Photonics 5, 1151–1163 (2018).
3. Acuna, G. P. et al. Fluorescence enhancement at docking sites of DNA-directed self-assembled nanoantennas. Science (80-. ). 338, 506–510 (2012).
4. Trofymchuk, K. et al. Addressable nanoantennas with cleared hotspots for single-molecule detection on a portable smartphone microscope. Nat. Commun. 12, 950 (2021).
5. Hübner, K. et al. Directing Single-Molecule Emission with DNA Origami-Assembled Optical Antennas. Nano Lett. (2019).
6. Raab, M., Vietz, C., Stefani, F. D., Acuna, G. P. & Tinnefeld, P. Shifting molecular localization by plasmonic coupling in a single-molecule mirage. Nat. Commun. 8, 13966 (2017). 

Register here to attend by Zoom.