Mina Yesilyurt | Leibniz Institute of Photonic Technology | Jena, Germany
Expertise: Finite-Difference Time-Domain simulation, dark-field microscopy, atomic force microscopy, DNA origami, nanoparticle functionalization
Directional plasmonic nanoantennas have been used in various applications by virtue of their ability to enhance light-matter interaction and to tailor emission patterns of quantum emitters. To obtain directionality, the morphology and spatial arrangement of nano-sized resonators must be precise at the nanoscale. So far, directional nanoantennas have been fabricated by top-down methods . In this work, DNA origami, a deterministic, cost-effective, scalable bottom-up technique is used to arrange gold nanoparticles (AuNPs) to obtain sub-10 nm scale interparticle distances (IPD, surface-to-surface distance) between AuNPs and directional photoluminescence from AuNPs. Figure 1 displays the scanning probe microscope and scanning electron microscope (SEM) images of the nanoantennas fabricated by DNA-origami method. In the inset of Fig. 1(a) the geometry of the antenna is shown: AuNPs are 15 nm in diameter but the IPD cannot be measured accurately due to the thickness of scanning tip. In Fig. 1(b) SEM images of the antennas from the same batch are shown: DNA-origami cannot be observed with SEM but center-to-center distances between AuNPs of the same structure can be measured and are indicated. As can be seen from the Fig. 1(b), IPD of sub-10 nm can be achieved by DNA-origami’s nm scale addressability.
 See et al. Nano Lett. 18 (2018), 6002-6008.