A nonlinear resonator is presented that enhances the bandwidth while providing high resonance amplitude. The nonlinear resonance circuit is comprised of an inductor electrically coupled to a capacitor, where either the inductor or capacitor is nonlinear. Response of the nonlinear resonance circuit to an excitation signal is described by a family of second-order differential equations with cubic-order nonlinearity, known as Duffing equations. In one aspect, the nonlinear resonator is implemented by a nonlinear dielectric resonator.