Vibrational Resonance in an Asymmetric Duffing oscillator

S. JEYAKUMARI, V. CHINNATHAMBI Department of Physics, Sri K.G.S. Arts College, Srivaikuntam 628 619, Tamilnadu, India., S. RAJASEKAR School of Physics, Bharathidasan University, Tiruchirapalli 620 024, Tamilnadu, India. [email protected], and M.A.F. SANJUAN Departamento de F́ısica, Universidad Rey Juan Carlos, Tulipán s/n, 28933 Móstoles, Madrid, Spain. [email protected] Abstract We analyze how the asymmetry of the potential well of the Duffing oscillator affects the vibrational resonance. We obtain, numerically and theoretically, the values of the low-frequency and amplitude of the high-frequency forces at which vibrational resonance occurs. Furthermore, we observe that an additional resonance is induced by the asymmetry of the potential well. We account the additional resonance in terms of resonant frequency of the slow motion of the system. Resonance occurs in the asymmetric system for the input signal frequency range for which it is not possible in the symmetric system. Resonance is also studied with nonsinusoidal input signals and in the presence of additive Gaussian white noise.