Nonlinear normal and anomalous response of non-interacting electric and magnetic dipoles subjected to strong AC and DC bias fields

W. T. Coffey (1) , Y. P. Kalmykov (2) , N. Wei (1)

1 Department of Electronic and Electrical Engineering
2 LAMPS - LAboratoire de Modélisation Pluridisciplinaire et Simulations

The perturbation theory approach via the Smoluchowski equation to the nonlinear dielectric relaxation of noninteracting permanent electric dipoles (Coffey and Paranjape, Proc R Ir Acad A 78:17, 1978) and the analogous Brownian magnetic relaxation of ferrofluids where Néel relaxation is ignored is revisited for the particular case of a strong dc bias field superimposed on a strong ac field. Unlike weak ac and strong bias dc fields, a frequency-dependent dc term now appears in the response as well as additional nonlinear terms at the fundamental and second harmonic frequencies. These may be experimentally observable particularly in the ferrofluid application. The corresponding results for the dc term for anomalous relaxation based on the fractional Smoluchowski equation are also given.

Mots clés: Nonlinear relaxation; Anomalous relaxation; Ferrofluids; Brownian motion; Debye theory

Domaines: Physique [physics]

W. T. Coffey, Y. P. Kalmykov, N. Wei. Nonlinear normal and anomalous response of non-interacting electric and magnetic dipoles subjected to strong AC and DC bias fields. Nonlinear Dynamics, 2014, 80 (4), pp.1861-1867. ⟨10.1007/s11071-014-1488-9⟩. ⟨hal-01143088⟩