2018 - Sustainable Industrial Processing Summit & Exhibition
4-7 November 2018, Rio Othon Palace, Rio De Janeiro, Brazil
| Magnetism in Micro and Nanostructures: Magnetic Recording and Magnonics João Paulo Sinnecker1; Elis Helena De Campos Pinto Sinnecker2; Danilo Froes Batista3; 1CENTRO BRASILEIRO DE PESQUISAS FíSICAS, Rio de Janeiro, Brazil; 2INSTITUTO DE FISICA, UFRJ, Rio de Janeiro, Brazil; 3CENTRO BRASILEIRO DE PESQUISAS FISICAS, Rio de Janeiro, Brazil; PAPER: 381/SISAM/Keynote (Oral) SCHEDULED: 15:55/Wed./Copacabana A (150/1st) ABSTRACT: This work will address the research in the area of micro and nanomagnetism, showing results in artificial magnetic micro and nanostructures for high-density magnetic recording and magnonics. New technological high-density storage systems investigations over the past decades have followed the study of artificial magnetic nanostructures as single storage elements. The reduction of the memory elements' size has been used to increase the storage density [1,2]. We have studied the magnetic behavior of T-shaped magnetic micro and nanostructures, experimentally and by micromagnetic simulations. T-shaped magnetic nanostructures have stable magnetic states resulting from the configurational anisotropy, in which stable magnetic states have been predicted for one single element, allowing the storage of two bits of information. Depending on the direction of the applied field, T-shapes can be prepared in four magnetic states. Magnonics is an emerging research field in which spin-waves are used for information transmission and processing. The data can be encoded either in the amplitude or phase, and the absence of charge transport eliminates Joule losses. Spin-wave propagation is usually done in patterned structures that require the continuous application of an external magnetic field, which jeopardizes its efficiency [3]. Magnetic domain walls as propagation channels have been proposed [4] as they exist in remnant magnetic states. The domain walls act as potential wells confining the spin-waves. We have simulated the spin-wave along 180° walls in permalloy slabs. We show that, up to 2 GHz, spin-waves are strongly confined within the wall. The dispersion relation for the confined waves resembles a magnetostatic-dominated Damon-Eschbach mode [5]. We have fabricated rectangular permalloy structures by electron-beam lithography and obtain Landau configuration reproducibly, as confirmed by Kerr microscopy images. This study is aimed to evaluate the suitability of these spin-waves for magnonics. References: [1] RA Escobar et al, Appl. Phys. Lett. 104, 123102 (2014) [2] RA Escobar et al, JAP 117, 223901 (2015) [3] E. Albisetti et al., AIP Advances 7, 055601 (2017) [4] F. Garcia-Sanchez et al., Phys. Rev. Lett. 114, 247206 (2015) [5] R. W. Damon and J. R. Eshbach, J. App. Phys. 31, S104 (1960) |
