{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,2]],"date-time":"2026-07-02T21:20:05Z","timestamp":1783027205402,"version":"3.54.6"},"reference-count":22,"publisher":"World Scientific Pub Co Pte Ltd","issue":"05","funder":[{"name":"Italian Ministry of University and Research","award":["2020PY8KTC"],"award-info":[{"award-number":["2020PY8KTC"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Int. J. Bifurcation Chaos"],"published-print":{"date-parts":[[2024,4]]},"abstract":"<jats:p> The aim of this paper is to present a novel class of time-dependent controls to realize ultra-fast magnetization switching in nanomagnets driven by spin-torques produced by spin-polarized electric currents. Magnetization dynamics in such complex systems is governed by the Landau\u2013Lifshitz\u2013Slonczewski equation which describes the precessional motion of (dimensionless) magnetization vector on the unit-sphere. The relevant case of nanoparticles with uniaxial anisotropy having in-plane easy and intermediate axes as well as out-of-plane hard axis is considered. By exploiting the characteristic smallness of damping and spin-torque intensity, the complexity of the magnetic system\u2019s dynamic is dealt with by employing tools borrowed from Hamiltonian Perturbation Theory. More precisely, the aforementioned controls are constructed via suitable perturbative tools in a way to realize approximate latitudinal solutions (i.e. motions on a sphere in which the out-of-plane magnetization component stays constant) with the effect to fast \u201cswitch\u201d the system from one stationary state to another. The possibility to keep a (\u201csmall\u201d) bounded value of the out-of-plane coordinate throughout this process of \u201ctransfer\u201d turns out to be advantageous in the applications as it sensibly reduces the post-switching relaxation oscillations that may cause the failure of switching in real samples. Further relevant quantitative results on the behavior of the solutions during the pre- and post-switching stages (termed \u201cexpulsion\u201d and \u201cattraction\u201d, respectively) are given as a by-product. A selection of validating numerical experiments is presented alongside the corresponding theoretical results. <\/jats:p>","DOI":"10.1142\/s0218127424500561","type":"journal-article","created":{"date-parts":[[2024,4,9]],"date-time":"2024-04-09T08:35:51Z","timestamp":1712651751000},"source":"Crossref","is-referenced-by-count":1,"title":["Controlled Quasi-Latitudinal Solutions for Ultra-Fast Spin-Torque Magnetization Switching"],"prefix":"10.1142","volume":"34","author":[{"ORCID":"https:\/\/orcid.org\/0009-0006-0132-1107","authenticated-orcid":false,"given":"Alessandro","family":"Fortunati","sequence":"first","affiliation":[{"name":"Department of Electrical Engineering and Information Technologies, University of Naples Federico II, I-80125 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5321-5772","authenticated-orcid":false,"given":"Massimiliano","family":"d\u2019Aquino","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Information Technologies, University of Naples Federico II, I-80125 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5224-1872","authenticated-orcid":false,"given":"Claudio","family":"Serpico","sequence":"additional","affiliation":[{"name":"Department of Electrical Engineering and Information Technologies, University of Naples Federico II, I-80125 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"219","published-online":{"date-parts":[[2024,4,9]]},"reference":[{"key":"S0218127424500561BIB001","doi-asserted-by":"publisher","DOI":"10.1109\/JPROC.2016.2590142"},{"key":"S0218127424500561BIB002","doi-asserted-by":"publisher","DOI":"10.1063\/1.3532960"},{"key":"S0218127424500561BIB003","series-title":"Interaction of Mechanics and Mathematics","volume-title":"Variational Principles of Continuum Mechanics: I. 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