Absorption cross-section spectroscopy of a single strong-coupling system between plasmon and molecular exciton resonance using a single silver nanoparticle dimer generating surface-enhanced resonant Raman scattering

Abstract

This study investigated spectral changes in the absorption cross-sections of single strong coupling systems composed of single silver nanoparticle dimers and a few dye molecules during the quenching of surface-enhanced resonant Raman scattering 2 (SERRS). The absorption cross-section was obtained by subtracting the scattering cross-section from an extinction cross-section. The spectral changes in these cross-sections were evaluated using a classical hybridization model composed of a plasmon and a molecular exciton including a molecular multi-level property. The changes in the scattering and extinction cross-sections exhibit blue-shifts in their peak energy and increased peak intensities, respectively, during SERRS quenching. These properties are effectively reproduced in the model by decreasing the coupling energy. In particular, the peaks in the scattering and extinction cross-sections appear as peaks or dips in the absorption cross-sections depending on the degree of scattering loss, which reflects the dimer sizes. These results are useful for optimizing photophysical and photochemical effects mediated by the electronic excited states of strong coupling systems.

Gold nanobipyramid-embedded ultrathin metal nanoframes for in situ monitoring catalytic reactions

“…The peak broadening and intensity reduction arise mainly from the increase of the size distribution upon the growth of the ultrathin metal nanoframes, because the starting Au NBPs are highly uniform in shape and size. 41,47 To further understand the nearly identical plasmon resonance before and aer the deposition of the ultrathin metal nanoframes, nite-difference time-domain (FDTD) simulations were performed to ascertain the plasmonic properties of the Au NBP-embedded ultrathin Au nanoframes (Fig. 2).…”

Toward a New Era of SERS and TERS at the Nanometer Scale: From Fundamentals to Innovative Applications

“…Itoh et al simultaneously measured the scattering and absorption spectral changes in the plasmon resonance and SERS during SERS quenching processes, using a single silver dimer (Figure a–d) . The modified coupled oscillator model, described in Section , consistently reproduced the changes with decreasing coupling energy from 200 to 0 meV . They also derived the enhancement and quenching factors from the coupling energy and quantitatively reproduced the SERS and SEF spectra, taking into consideration the ultrafast electronic dynamics (Figure e,f) .…”

“…They derived a coupling energy in the range of 115–200 meV from the anticrossing in the hybridized resonance using the coupled oscillator model, as discussed in Section . Itoh et al simultaneously measured the scattering and absorption spectral changes in the plasmon resonance and SERS during SERS quenching processes, using a single silver dimer (Figure a–d) . The modified coupled oscillator model, described in Section , consistently reproduced the changes with decreasing coupling energy from 200 to 0 meV .…”

Exploiting clock transitions for the chemical design of resilient molecular spin qubits

“…It can equally be used to automatically explore physical or chemical modications of any kind of systems presenting anticrossings, independently of the nature of the noise. The model employed herein can be applied to facilitate the detection of anticrossings in a number of elds, from the theoretical molecular design of strong coupling between plasmons and single-molecule excitons 56,57 to the prediction of the electronic and optical properties of twisted bilayer graphene. 58 As a nal remark, the present work serves as a rst numerical estimate of the sensitivity to structural or vibrational distortions of different kinds of CTs.…”