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Updated: Jun 14, 2026

Measurement of Scattering Nonlinearities from a Single Plasmonic Nanoparticle
Published on: January 3, 2016
Reconstructing nonlinearities with intermodulation spectroscopy
Carsten Hutter1, Daniel Platz, E A Tholén
1Department of Physics, Stockholm University, AlbaNova, SE-106 91 Stockholm, Sweden.
Abstract:
We describe a method of analysis which allows for reconstructing the nonlinear disturbance of a high Q harmonic oscillator. When the oscillator is driven with two or more frequencies, the nonlinearity causes intermodulation of the drives, resulting in a complicated spectral response. Analysis of this spectrum allows one to approximate the nonlinearity. The method, which is generally applicable to measurements based on resonant detection, increases the information content of the measurement without requiring a large detection bandwidth, and optimally uses the enhanced sensitivity near resonance to extract information and minimize error due to detector noise.
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