Physica A 286 (2000) 283–291 www.elsevier.com/locate/physa Multifractal spectra of magnetostatic spin waves in quasiperiodic magnetic multilayers Dory H.A.L. Anselmo a , Gil A. Farias a , R.N. Costa a , E.L. Albuquerque b; a Departamento de F sica, Universidade Federal do Cear a, Campus do Pici, Fortaleza-CE 60455-760, Brazil b Departamento de F sica, Universidade Federal do Rio Grande do Norte, Natal-RN 59072-970, Brazil Received 25 April 2000 Abstract A multifractal analysis for bulk spin waves propagating in quasiperiodic magnetic multilayers is carried out in the magnetostatic regime. Numerical results are obtained by considering their propagation in these articial structures arranged in the Fibonacci, Thue –Morse and double-period sequences. An analysis for the behavior of the scaling exponent (the diusion constant of the spectra) versus the in-plane wavevector K is also done, leading to interesting results. The spectra are obtained for quasiperiodic structures based on the ferromagnet crystal Fe and the antiferromagnet crystal MnF 2. c 2000 Elsevier Science B.V. All rights reserved. PACS: 75.70.C; 75.30.D; 68.65; 02.30.L Keywords: Fractals; Magnetostatic spin waves; Quasiperiodic systems 1. Introduction Since the introduction of Fractals in early 1980s, complex structures have been studied by using a dierent concept, namely the fractal dimension [1,2]. The use of multifractal and monofractal analysis has proved to be an important tool to simulate (in many cases with impressive agreement with experimental data) real systems [3– 6]. On the other hand, the discovery of quasicrystals by Shechtman et al. [7] has recently attracted a lot of attention, both theoretically [8,9] and experimentally [10,11]. One of the reasons for that is because quasiperiodic systems lie in a spot just between the * Corresponding author. Fax: +55-84-2119217. E-mail address: ela@dfte.ufrn.br (E.L. Albuquerque). 0378-4371/00/$ - see front matter c 2000 Elsevier Science B.V. All rights reserved. PII: S0378-4371(00)00297-1