Nonlinear sensing and oscillators with exceptional points

Systems with exceptional points (EP) have the unique physics-based property associated with the degeneracy of at least two eigenmodes that leads to ultra sensitivity when such system is perturbed. Though EP is also negatively affected by noise, we show that using nonlinear active components improves several aspects of EP circuits. When brought slightly above their oscillating threshold, the oscillation frequency is highly sensitive to perturbation. The spectrum has a very narrow line width and exhibits very low phase noise. Various theoretical and experimental examples will be shown discussing the sensitivity to perturbation.