ARTICLE IN PRESS Superlattices and Microstructures ( ) – Contents lists available at ScienceDirect Superlattices and Microstructures journal homepage: www.elsevier.com/locate/superlattices Novel ultrasonic-assisted alignment of L1 0 FePt nanoparticles S. Foglia a,∗ , A. Notargiacomo a , A. Capobianchi b , A.M. Testa b , D. Fiorani b , L. Arrizza c , C. Veroli d a Istituto di Fotonica e Nanotecnologie, CNR, 00146 Roma, Italy b Istituto di Struttura della Materia, CNR, Montelibretti, Roma, Italy c Università degli Studi dell’Aquila, Centro di Microscopia Elettronica, L’Aquila, Italy d Istituto di Studio Materiali Nanostrutturati, CNR, Montelibretti, Roma, Italy article info Article history: Available online xxxx Keywords: Magnetic nanoparticles Assembling abstract Chemically ordered (L1 0 ) FePt nanoparticles were synthesized by a microemulsion technique and the ordered phase was obtained by heating a mixture of particles and lyophilized NaCl as the separating medium, avoiding coalescence. A chloroform suspension of L1 0 FePt nanoparticles was evaporated at room temperature, assisted by ultrasonic vibration, producing the arrangement of the particles on the substrate. Parallel lines and flower-like patterns were obtained, starting from a 4 × 10 −3 M suspension and using higher dilutions, suggesting that the fast evaporation of chloroform allows the particles deposition on the substrate, following the propagation direction of the ultrasound waves and/or placement at a vibration node, depending on the concentration. © 2008 Elsevier Ltd. All rights reserved. FePt-based nanostructured materials are promising candidates for future ultrahigh density recording media because of their good chemical stability and high magnetocrystalline anisotropy (∼10 8 erg/cm 3 ) observed in the ordered face-centred tetragonal (fct) L1 0 phase [1,2]. This large magnetocrystalline anisotropy allows nanometric grains to be thermally stable over typical data storage periods of 10 years. A well-organized magnetic array of such particles should contribute to efforts to design magnetic media capable of increasing densities well beyond 1 Tbit/in 2 [3]. ∗ Corresponding author. Tel.: +39 0657333343. E-mail address: sabrina.foglia@ism.cnr.it (S. Foglia). 0749-6036/$ – see front matter © 2008 Elsevier Ltd. All rights reserved. doi:10.1016/j.spmi.2008.11.001 Please cite this article in press as: S. Foglia, et al., Novel ultrasonic-assisted alignment of L1 0 FePt nanoparticles, Superlattices and Microstructures (2008), doi:10.1016/j.spmi.2008.11.001