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Chiroptical spectroscopy of a freely diffusing single nanoparticle.

ABSTRACT: Chiral plasmonic nanoparticles can exhibit strong chiroptical signals compared to the corresponding molecular response. Observations are, however, generally restricted to measurements on stationary single particles with a fixed orientation, which complicates the spectral analysis. Here, we report the spectroscopic observation of a freely diffusing single chiral nanoparticle in solution. By acquiring time-resolved circular differential scattering signals we show that the spectral interpretation is significantly simplified. We experimentally demonstrate the equivalence between time-averaged chiral spectra observed for an individual nanostructure and the corresponding ensemble spectra, and thereby demonstrate the ergodic principle for chiroptical spectroscopy. We also show how it is possible for an achiral particle to yield an instantaneous chiroptical response, whereas the time-averaged signals are an unequivocal measure of chirality. Time-resolved chiroptical spectroscopy on a freely moving chiral nanoparticle advances the field of single-particle spectroscopy, and is a means to obtain the true signature of the nanoparticle's chirality.

SUBMITTER: Sachs J

PROVIDER: S-EPMC7481242 | biostudies-literature | 2020 Sep

REPOSITORIES: biostudies-literature

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Chiroptical spectroscopy of a freely diffusing single nanoparticle.

Sachs Johannes J Günther Jan-Philipp JP Mark Andrew G AG Fischer Peer P

Nature communications 20200909 1

Chiral plasmonic nanoparticles can exhibit strong chiroptical signals compared to the corresponding molecular response. Observations are, however, generally restricted to measurements on stationary single particles with a fixed orientation, which complicates the spectral analysis. Here, we report the spectroscopic observation of a freely diffusing single chiral nanoparticle in solution. By acquiring time-resolved circular differential scattering signals we show that the spectral interpretation i ...[more]

PMID: 32908138

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Chiroptical spectroscopy of a freely diffusing single nanoparticle.

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Chiroptical spectroscopy of a freely diffusing single nanoparticle.

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