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Updated: Nov 3, 2025

Implementation of a Reference Interferometer for Nanodetection
Published on: April 26, 2014
Enhanced avionic sensing based on Wigner's cusp anomalies
Rodion Kononchuk1, Joshua Feinberg2, Joseph Knee3
1Wave Transport in Complex Systems Laboratory, Department of Physics, Wesleyan University, Middletown, CT 06459, USA.
Abstract:
Typical sensors detect small perturbations by measuring their effects on a physical observable, using a linear response principle (LRP). It turns out that once LRP is abandoned, new opportunities emerge. A prominent example is resonant systems operating near Nth-order exceptional point degeneracies (EPDs) where a small perturbation ε ≪ 1 activates an inherent sublinear response [Formula: see text] in resonant splitting. Here, we propose an alternative sublinear optomechanical sensing scheme that is rooted in Wigner's cusp anomalies (WCAs), first discussed in the framework of nuclear reactions: a frequency-dependent square-root singularity of the differential scattering cross section around the energy threshold of a newly opened channel, which we use to amplify small perturbations. WCA hypersensitivity can be applied in a variety of sensing applications, besides optomechanical accelerometry discussed in this paper. Our WCA platforms are compact, do not require a judicious arrangement of active elements (unlike EPD platforms), and, if chosen, can be cavity free.
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