RT info:eu-repo/semantics/article T1 Magnetisation switching of FePt nanoparticle recording medium by femtosecond laser pulses A1 John, R. . A1 Berritta, M. . A1 Hinzke, D. . A1 Müller, C. . A1 Santos, T. . A1 Ulrichs, H. . A1 Nieves Cordones, Pablo A1 Walowski, J. . A1 Mondal, R. . A1 Chubykalo Fesenko, O. A1 McCord, J. . A1 Oppeneer, P. M. . A1 Nowak, U. . A1 Münzenberg, M. . AB Manipulation of magnetisation with ultrashort laser pulses is promising for information storage device applications. The dynamics of the magnetisation response depends on the energy transfer from the photons to the spins during the initial laser excitation. A material of special interest for magnetic storage are FePt nanoparticles, for which switching of the magnetisation with optical angular momentum was demonstrated recently. The mechanism remained unclear. Here we investigate experimentally and theoretically the all-optical switching of FePt nanoparticles. We show that the magnetisation switching is a stochastic process. We develop a complete multiscale model which allows us to optimize the number of laser shots needed to switch the magnetisation of high anisotropy FePt nanoparticles in our experiments. We conclude that only angular momentum induced optically by the inverse Faraday effect will provide switching with one single femtosecond laser pulse. PB Nature Publishing Group SN 2045-2322 YR 2017 FD 2017-06 LK http://hdl.handle.net/10259/4764 UL http://hdl.handle.net/10259/4764 LA eng NO EC under Contract No. 281043, FemtoSpin. The work at Greifswald Universitywas supported by the German research foundation (DFG), projects MU MU 1780/8-1, MU 1780/10-1. Researchat Göttingen University was supported via SFB 1073, Projects A2 and B1. Research at Uppsala University wassupported by the Swedish Research Council (VR), the Röntgen-Ångström Cluster, the Knut and Alice WallenbergFoundation (Contract No. 2015.0060), and Swedish National Infrastructure for Computing (SNIC). Research atKiel University was supported by the DFG, projects MC 9/9-2, MC 9/10-2. P.N. acknowledges support from EUHorizon 2020 Framework Programme for Research and Innovation (2014-2020) under Grant Agreement No.686056, NOVAMAG. The work in Konstanz was supported via the Center for Applied Photonics. DS Repositorio Institucional de la Universidad de Burgos RD 29-mar-2024