PERSPECTIVES
FOLDING DNA
FOLDING DNA TO CONTROL LIGHT AT THE NANOSCALE
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Maria SANZ-PAZ 1, *, Karol KOŁĄTAJ 2 and Guillermo P. ACUNA 2, *
1
Sorbonne Université, CNRS, Institut des NanoSciences de Paris, INSP, F-75252 Paris, France
2
Department of Physics, University of Fribourg, Chemin du Musée 3, Fribourg CH-1700, Switzerland * maria. sanz-paz @ insp. upmc. fr, guillermo. acuna @ unifr. ch
https:// doi. org / 10.1051 / photon / 202614066
Controlling light at the nanoscale is central to nanophotonics. Despite its broad impact, topdown lithography fabrication remains constrained by resolution, stoichiometry, material losses, and scalability. DNA nanotechnology offers a complementary bottom-up route: DNA origami, a programmable breadboard with nanometer addressability, enables deterministic assembly of nanoparticles and quantum emitters into optical structures, including single-molecule antennas and 3D chiral plasmonic systems.
This is an Open Access article distributed under the terms of the Creative Commons Attribution License( https:// creativecommons. org / licenses / by / 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
Nanophotonics aims to control and manipulate light at scales well below the diffraction limit. Tailoring light – matter interactions at the nanometer scale requires concentrating electromagnetic fields into extremely small volumes. Optical antennas provide one route to this goal by converting freely propagating light into tightly confined near fields. When single-photon emitters, such as organic fluorophores or quantum dots, are positioned within these plasmonic hotspots, their optical environment can be strongly modified. As a result, optical antennas can accelerate decay rates, enhance brightness, and direct emission into specific directions.
Optical antennas are traditionally fabricated using top-down techniques, including electron- and ion-beam lithography. These methods have enabled a wide range of antenna geometries and have been essential for studying their interaction with quantum emitters. However, they also present important limitations for advanced nanophotonics. First, positioning a single emitter within an antenna geometry with nanometer precision remains exceptionally difficult. Second, lithographic metals are often polycrystalline and display surface roughness, which can reduce optical quality.
Third, complex architectures, including three-dimensional nanostructures and multi-material assemblies, remain challenging to realize. Finally, despite continuous progress, top-down nanofabrication is often slow, serial, and costly.
Bottom-up self-assembly offers a complementary route to overcome these limitations. Among DNA-based strategies, DNA origami has emerged as a particularly versatile nanofabrication platform. Using Watson-Crick base pairing, DNA strands can be folded into prescribed shapes, creating fully addressable molecular breadboards with nanometer precision. By organizing optical elements, such as nanoparticles( NPs) and
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