Month: August 2019

Launching of hyperbolic phonon-polaritons in h-BN slabs by resonant metal plasmonic antennas

Launching and manipulation of polaritons in van der Waals materials offers novel opportunities for applications such as field-enhanced molecular spectroscopy and photodetection.*

Particularly, the highly confined hyperbolic phonon polaritons (HPhPs) in h-BN slabs attract growing interest for their capability of guiding light at the nanoscale. An efficient coupling between free space photons and HPhPs is, however, hampered by their large momentum mismatch.*

In the article “Launching of hyperbolic phonon-polaritons in h-BN slabs by resonant metal plasmonic antennas” P. Pons-Valencia, F. J. Alfaro-Mozaz, M. M. Wiecha, V. Biolek, I. Dolado, S. Vélez,P. Li, P. Alonso-González, F. Casanova, L. E. Hueso, L. Martín-Moreno, R. Hillenbrand and A. Y. Nikitin show that resonant metallic antennas can efficiently launch HPhPs in thin h-BN slabs. Despite the strong hybridization of HPhPs in the h-BN slab and Fabry-Pérot plasmonic resonances in the metal antenna, the efficiency of launching propagating HPhPs in h-BN by resonant antennas exceeds significantly that of the non-resonant ones.

Their results provide fundamental insights into the launching of HPhPs in thin polar slabs by resonant plasmonic antennas, which will be crucial for phonon-polariton based nanophotonic devices.*

A commercial s-SNOM setup in which the oscillating (at a frequency Ω≅270kHz) metal-coated (Pt/Ir) AFM tip (NanoWorld ARROW-NCPt) was illuminated by p-polarized mid-IR radiation, was used.*

Figure 4 from “Launching of hyperbolic phonon-polaritons in h-BN slabs by resonant metal plasmonic antennas” by P. Pns-Valencia et al. : Near-field imaging of the HPhPs launched by the gold antenna. a Schematics of the s-SNOM setup. b Illustration of antenna launching of HPhPs. The spatial distribution of the near-field (shown by the red and blue colors) is adapted from the simulation of Re(Ez). c Topography of the antenna. d Simulated near-field distribution, |E(x, y)|, created by the rod antenna on CaF2 (the field is taken at the top surface of the antenna). Scale bars in c, d are 0.5 μm. e, h Experimental near-field images. f, i Simulated near-field distribution |Ez(x, y)| (taken 150 nm away from the h-BN slab). g, j Simulated near-field distribution |Ez(z, y)| taken in the cross-section plane along the center of the rod antenna. In e–g ω = 1430 cm−1, while in h–j ω = 1515 cm−1. The scale bars in e–i are 2 μm and in g, j are 0.1 μm (vertical) and 0.5 μm (horizontal). The length of the antenna in all panels is L = 2.29 μm

Figure 4 from “Launching of hyperbolic phonon-polaritons in h-BN slabs by resonant metal plasmonic antennas” by P. Pons-Valencia et al. :
Near-field imaging of the HPhPs launched by the gold antenna. a Schematics of the s-SNOM setup. b Illustration of antenna launching of HPhPs. The spatial distribution of the near-field (shown by the red and blue colors) is adapted from the simulation of Re(Ez). c Topography of the antenna. d Simulated near-field distribution, |E(x, y)|, created by the rod antenna on CaF2 (the field is taken at the top surface of the antenna). Scale bars in c, d are 0.5 μm. e, h Experimental near-field images. f, i Simulated near-field distribution |Ez(x, y)| (taken 150 nm away from the h-BN slab). g, j Simulated near-field distribution |Ez(z, y)| taken in the cross-section plane along the center of the rod antenna. In e–g ω = 1430 cm−1, while in h–j ω = 1515 cm−1. The scale bars in e–i are 2 μm and in g, j are 0.1 μm (vertical) and 0.5 μm (horizontal). The length of the antenna in all panels is L = 2.29 μm

*P. Pons-Valencia, F. J. Alfaro-Mozaz, M. M. Wiecha, V. Biolek, I. Dolado, S. Vélez,P. Li, P. Alonso-González, F. Casanova, L. E. Hueso, L. Martín-Moreno, R. Hillenbrand, A. Y. Nikitin
Launching of hyperbolic phonon-polaritons in h-BN slabs by resonant metal plasmonic antennas
Nature Communications 2019; 10: 3242
doi: 10.1038/s41467-019-11143-7

Please follow this external link to read the full article: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6642108/

Open Access: The paper « Launching of hyperbolic phonon-polaritons in h-BN slabs by resonant metal plasmonic antennas » by P. Pons-Valencia, F. J. Alfaro-Mozaz, M. M. Wiecha, V. Biolek, I. Dolado, S. Vélez,P. Li, P. Alonso-González, F. Casanova, L. E. Hueso, L. Martín-Moreno, R. Hillenbrand and A. Y. Nikitin is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.

ChinaNano 2019 Beijing August 17-19, Booth 218

To all members of the #AFMcommunity who have also travelled to Beijing to participate in the ChinaNano 2019 conference this week: Welcome at our booth 218 at the ChinaNano 2019! We hope you have some time left to drop in and let us know about the progress of your research.

Looking forward to meeting you at the ChinaNano 2019

Effect of Staple Age on DNA Origami Nanostructure Assembly and Stability

DNA origami nanostructures are widely employed in various areas of fundamental and applied research. Due to the tremendous success of the DNA origami technique in the academic field, considerable efforts currently aim at the translation of this technology from a laboratory setting to real-world applications, such as nanoelectronics, drug delivery, and biosensing. While many of these real-world applications rely on an intact DNA origami shape, they often also subject the DNA origami nanostructures to rather harsh and potentially damaging environmental and processing conditions.*

In their article “Effect of Staple Age on DNA Origami Nanostructure Assembly and Stability” Charlotte Kielar, Yang Xin, Xiaodan Xu, Siqi Zhu, Nelli Gorin , Guido Grundmeier, Christin Möser, David M. Smith and Adrian Keller investigate the effect of long-term storage of the employed staple strands on DNA origami assembly and stability.*

Atomic force microscopy (AFM) under liquid and dry conditions was employed to characterize the structural integrity of Rothemund triangles assembled from different staple sets that have been stored at −20 °C for up to 43 months.*

NanoWorld Ultra-Short Cantilevers USC-F0.3-k0.3 were the AFM probes that were used for the AFM measurements under liquid conditions.*

Figure 1. from “Effect of Staple Age on DNA Origami Nanostructure Assembly and Stability” by Charlotte Kielar et al.
(a) Schematic illustration of the Rothemund triangle DNA origami. AFM images of DNA origami triangles assembled from staple sets aged for (b) 2–7 months, (c) 11–16 months, (d) 22–27 months, and (e) 38–43 months. Measurements were performed either in liquid (left column) or dry conditions after gently dipping the sample into water (central column) or after harsh rinsing (right column). Scale bars represent 250 nm. Height scales are given in the individual images. The insets show zooms of individual DNA origami triangles.

*Charlotte Kielar, Yang Xin, Xiaodan Xu, Siqi Zhu, Nelli Gorin , Guido Grundmeier, Christin Möser, David M. Smith and Adrian Keller
Effect of Staple Age on DNA Origami Nanostructure Assembly and Stability
Molecules 2019, 24(14), 2577
doi: https://doi.org/10.3390/molecules24142577

Please follow this external link to the full article: https://www.mdpi.com/1420-3049/24/14/2577/htm

Open Access: The article « Effect of Staple Age on DNA Origami Nanostructure Assembly and Stability » by Charlotte Kielar, Yang Xin, Xiaodan Xu, Siqi Zhu, Nelli Gorin , Guido Grundmeier, Christin Möser, David M. Smith and Adrian Keller is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/.