Mechanically Tunable Lattice‐Plasmon Resonances by Templated Self‐Assembled Superlattices for Multi‐Wavelength Surface‐Enhanced Raman Spectroscopy

Abstract

the plasmon resonance wavelength and the excitation source. [3,4] Plasmon resonances can be engineered through nanostructure composition and morphology, as well as the refractive index of the environment. [5,6] In the case of superlattices, for example in the form of periodically arranged clusters of gold nanoparticles, another control parameter comes into play, [7] namely the lattice period. Lattice resonances result from diffractively coupled localized surface plasmons of a substructure within a periodic arrangement. [8] The periodicity, the center-to-center distance between adjacent plasmonic meta-atoms, is the key parameter for constructive (radiative) far-field coupling.In the case of resonant excitation, lattice plasmons can generate intense electromagnetic fields, [9][10][11] as required for ultrasensitive SERS spectroscopy. We have recently shown that the resonance band of square-array 2D supercrystals, fabricated by template-assisted colloidal selfassembly of gold nanoparticles (NPs), can be tuned throughout the visible and near-infrared (NIR) range, as a function of the lattice parameter. [12] The highest SERS performance was achieved at best match with the laser excitation. Combining short-and long-range interactions in such arrays can result in higher field enhancements. Tuning both the lattice period and the size of the substructures requires iterative remodeling of

Tunable surface plasmon resonance enhanced fluorescence via the stretching of a gold quantum dot-coated aluminum-coated elastomeric grating substrate

“…In this study, the fluorescence intensity of AuQDs was controlled by shifting the SPR-excitation wavelength by stretching an Al-coated PDMS-grating substrate. In this process, not only was the SPR wavelength tuned, as previously reported, 33,34,52,53 but the SPF was also tuned. The SPR-excitation wavelength of the Al-coated PDMS-grating substrate was tuned by changing the incident light angle, from 5° to 60°, and stretching the sample from 0 to 1.0 mm.…”

Prospects of Surface-Enhanced Raman Spectroscopy for Biomarker Monitoring toward Precision Medicine

“… 67 , 117 In a variation of the same method, the plasmonic substrates were transferred onto elastomeric PDMS-based supports, thereby allowing real-time modification of the lattice plasmon resonances by extension or contraction of the substrate upon application of macroscopic strain ( Figure 3 b). 118 …”

“…(b) The optical response of AuNP arrays can be dynamically tuned by applying extension or contraction forces onto flexible plasmonic substrates. Reproduced with permission from ref ( 118 ). Copyright Wiley-VCH 2021.…”

Large-area Co(OH)2 nanoflower array films decorated with Ag nanoparticles as sensitive SERS substrates

“…[19][20][21][22] For practical applications, SERS substrates with high SERS activity and good signal uniformity are highly demanded. In order to achieve high SERS sensitivity and good signal uniformity, large-area well-ordered plasmonic nanostructure arrays have been manufactured by various methods, such as template-assisted methods, [23][24][25] photolithography, 26 electron beam lithography, [27][28][29] nanoimprint lithography 30 and femtosecond laser printing. 31,32 However, the abovementioned methods require expensive equipment or complicated manufacturing processes, leading to a high threshold for fabricating large-area well-ordered plasmonic nanostructures.…”