Influence of Nonlinearity on an Exceptional Point in a System of Coupled Duffing Oscillators

The effect of nonlinearity on the displacement of an exceptional point in a system of two coupled Duffing oscillators with a change in the coupling coefficients and insertion loss was researched. It is shown that the displacement of the exceptional point with a change in the nonlinearity coefficient is accompanied by a decrease in the amplitude of the excited oscillations and a shift in the resonant frequency. The threshold values of the coefficients of nonlinearity, coupling, and insertion loss at which the exceptional point appears are numerically found. It is shown that an increase in the nonlinearity coefficient leads to a decrease in the threshold value of the insertion loss required for the formation of the exceptional point.