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arXiv · 1609.05032

Measurement of second-order response without perturbation

Laurent Helden·Urna Basu·Matthias Krüger·Clemens Bechinger
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Abstract

We study the second order response functions of a colloidal particle being subjected to an anharmonic potential. Contrary to typical response measurements which require an external perturbation, here we experimentally confirm a recently developed approach where the system's susceptibilities up to second order are obtained from the particle's equilibrium trajectory [PCCP $\mathrm{{\bf 17}}$, 6653 (2015)]. The measured susceptibilities are in quantitative agreement with those obtained from the response to an external perturbation.

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Laurent Helden, Urna Basu, Matthias Krüger, Clemens Bechinger. 2016-09-16. Measurement of second-order response without perturbation. https://doi.org/10.1209/0295-5075/116/60003

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