Resonant Optical Antennas with Atomic-Sized Tips and Tunable Gaps Achieved by Mechanical Actuation and Electrical Control

Gruber, Cynthia; Herrmann, Lars O.; Bellido, Edson P.; Dössegger, Janine; Olziersky, Antonis; Drechsler, Ute; Puebla‐Hellmann, Gabriel; Botton, Gianluigi A.; Novotny, Lukas; Lörtscher, Emanuel

doi:10.1021/acs.nanolett.0c01072

Cited by 12 publications

(18 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Gruber et al demonstrated that the gap size of plasmonic structures fabricated by electron-beam lithography can be varied in the sub-nanometer scale using mechanical strain actuation and electrical control. [263] Optical scattering spectra revealed a redshift associated with the gap size decrease and a blueshift for gaps under 0.3 nm. Hence, this approach is a promising platform for the investigation of the optical properties of various nanostructure designs attainable by top-down methods.…”

Section: Gap Sizementioning

confidence: 94%

Synthesis, Assembly, Optical Properties, and Sensing Applications of Plasmonic Gap Nanostructures

Kim

Lee

et al. 2021

Advanced Materials

View full text Add to dashboard Cite

sharp-tip structures with a highly focused field at the end of the tip. [7] In particular, plasmonic gap nanostructures (PGNs) are among the most promising materials for diverse applications with highly localized field and amplified optical signals in the gap including sensing, spectroscopy, optics, biomedicine, electronics, and energy applications. [8][9][10][11][12][13] The development of bottom-up or top-down synthetic methods enabled the access to numerous nanogap structures with diverse gap sizes, morphologies, and compositions. [14][15][16][17][18] The highly localized electric field inside the plasmonic nanogap and the appearance of plasmonic coupling in closely neighboring structures have been studied, leading to the discovery of interesting optical phenomena and advances in sensing such as ultrasensitive spectroscopy, singlemolecule sensing methods, and in situ detection techniques. [19][20][21] As small changes in the distance, morphology, and composition of the nanogap lead to significant variations in the optical responses, the highly precise, controllable, and high-yielding preparation of PGNs is important to achieve reproducible and reliable results. However, although numerous pioneering studies on basic synthetic methods, characteristics, and applications enabled the understanding and control over plasmonic nanogaps, key challenges still remain for the practical use and applications of PGNs. In particular, the sub-nanometer, atomic-level control of the nanogap, coupled with the scaling-up issue, and its fundamental understanding have not yet been fully accomplished. For example, in surfaceenhanced Raman spectroscopy (SERS) using plasmonic gaps, early research focused on a high enhancement factor (EF). In contrast, recent studies revealed that a deep understanding at atomic scale is required, as differences in the small regime such as picocavities or molecular orientation can have a large effect on the signal. [22][23][24] Hence, a comprehensive understanding of the nanogap is critical to the further development of the field.This progress report addresses emerging issues and challenges in the field of nanogap-based plasmonics and plasmonic nanomaterials. We first describe the challenges in the creation of intra-or intergaps by bottom-up or top-down synthesis, and discuss breakthroughs that allow for overcoming these obstacles. Next, optical properties according to gap size, morphology, and composition are summarized to provide insight into the nature of gap plasmonics. The discussion of applications in this article mainly highlights surface-enhanced Plasmonic gap nanostructures (PGNs) have been extensively investigated mainly because of their strongly enhanced optical responses, which stem from the high intensity of the localized field in the nanogap. The recently developed methods for the preparation of versatile nanogap structures open new avenues for the exploration of unprecedented optical properties and development of sensing applications relying on the amplification of various optical signals....

show abstract

Section: Gap Sizementioning

confidence: 94%

Synthesis, Assembly, Optical Properties, and Sensing Applications of Plasmonic Gap Nanostructures

Kim

Lee

et al. 2021

Advanced Materials

View full text Add to dashboard Cite

show abstract

“…Over the years, there have been many reports on the realization of measurement setups and geometries with inherent stability against mechanical vibrations, e.g., to investigate electrical and thermal conductivity of single molecules and atoms [41][42][43][44][45][46][47]. These structures reach subnanometer precision in one dimension, but they have not demonstrated lateral scanning and positioning of a nanoprobe against a sample.…”

Section: Discussionmentioning

confidence: 99%

A robust tip-less positioning device for near-field investigations: Press and Roll Scan (PROscan)

Liu¹,

Becker²,

Matsuzaki³

et al. 2022

Preprint

View full text Add to dashboard Cite

Scanning probe microscopes scan and manipulate a sharp tip in the immediate vicinity of a sample surface. The limited bandwidth of the feedback mechanism used for stabilizing the separation between the tip and the sample makes the fragile nanoscopic tip very susceptible to mechanical instabilities. We propose, demonstrate and characterize a new alternative device based on bulging a thin substrate against a second substrate and rolling them with respect each other. We showcase the power of this method by placing gold nanoparticles and semiconductor quantum dots on the two opposite substrates and positioning them with nanometer precision to enhance the fluorescence intensity and emission rate. We exhibit the passive mechanical stability of the system over more than one hour. The design concept presented in this work holds promise in a variety of other contexts, where nanoscopic features have to be positioned and kept near contact with each other.

show abstract

“…used insulating nanoimprint polymer as the sacrificial layer, which was removed after plasma etching and thus made the Au electrodes suspended and elevated, as shown in Figure 6c. [ 44 ]…”

Section: Fabrication Of On‐chip Molecular Junctions Based On Micro‐elmentioning

confidence: 99%

Application of Micro/Nanofabrication Techniques to On‐Chip Molecular Electronics

Zheng

Shi

et al. 2021

Small Methods

View full text Add to dashboard Cite

Molecular electronics is a promising subject to overcome the size limitation of silicon‐based electronic devices. In the past decades, various micro/nanofabrication techniques have been developed for constructing molecular junctions, and a number of breakthroughs are made in the characterizations and applications of the single‐molecule device. The history and progress are reviewed in this article, laying emphasis on the recent works on the combination of micro/nanofabrication techniques with other techniques such as electrochemical deposition and surface‐enhanced Raman spectroscopy (SERS). Some prototypical single‐molecule devices such as molecular transistors are presented. Finally, the challenges and prospects in the fabrication of single‐molecule devices are discussed.

show abstract

Resonant Optical Antennas with Atomic-Sized Tips and Tunable Gaps Achieved by Mechanical Actuation and Electrical Control

Cited by 12 publications

References 43 publications

Synthesis, Assembly, Optical Properties, and Sensing Applications of Plasmonic Gap Nanostructures

Synthesis, Assembly, Optical Properties, and Sensing Applications of Plasmonic Gap Nanostructures

A robust tip-less positioning device for near-field investigations: Press and Roll Scan (PROscan)

Application of Micro/Nanofabrication Techniques to On‐Chip Molecular Electronics

Contact Info

Product

Resources

About