{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,17]],"date-time":"2026-04-17T17:55:43Z","timestamp":1776448543879,"version":"3.51.2"},"reference-count":40,"publisher":"MDPI AG","issue":"14","license":[{"start":{"date-parts":[[2023,7,19]],"date-time":"2023-07-19T00:00:00Z","timestamp":1689724800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["11204044"],"award-info":[{"award-number":["11204044"]}]},{"name":"National Natural Science Foundation of China","award":["12074285"],"award-info":[{"award-number":["12074285"]}]},{"name":"National Natural Science Foundation of China","award":["2020A1515010411"],"award-info":[{"award-number":["2020A1515010411"]}]},{"name":"National Natural Science Foundation of China","award":["2023A03J0125"],"award-info":[{"award-number":["2023A03J0125"]}]},{"name":"Guangdong Basic and Applied Basic Research Foundation","award":["11204044"],"award-info":[{"award-number":["11204044"]}]},{"name":"Guangdong Basic and Applied Basic Research Foundation","award":["12074285"],"award-info":[{"award-number":["12074285"]}]},{"name":"Guangdong Basic and Applied Basic Research Foundation","award":["2020A1515010411"],"award-info":[{"award-number":["2020A1515010411"]}]},{"name":"Guangdong Basic and Applied Basic Research Foundation","award":["2023A03J0125"],"award-info":[{"award-number":["2023A03J0125"]}]},{"name":"Guangzhou Science and Technology Planning Project","award":["11204044"],"award-info":[{"award-number":["11204044"]}]},{"name":"Guangzhou Science and Technology Planning Project","award":["12074285"],"award-info":[{"award-number":["12074285"]}]},{"name":"Guangzhou Science and Technology Planning Project","award":["2020A1515010411"],"award-info":[{"award-number":["2020A1515010411"]}]},{"name":"Guangzhou Science and Technology Planning Project","award":["2023A03J0125"],"award-info":[{"award-number":["2023A03J0125"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The fundamental mechanisms of ultrafast demagnetization and magnetization recovery processes in ferromagnetic materials remain incompletely understood. The investigation of different dynamic features which depend on various physical quantities requires a more systematic approach. Here, the femtosecond laser-induced demagnetization and recovery dynamics in L10-Fe0.5Pt0.5 alloy film are studied by utilizing time-resolved magneto-optical Kerr measurements, focusing on their dependences of excitation fluence and ambient temperature over broad ranges. Ultrafast demagnetization dominated by Elliott-Yafet spin-flip scattering, and two-step magnetization recovery processes are found to be involved in all observations. The fast recovery time corresponding to spin\u2013lattice relaxation is much shorter than that of many ferromagnets and increase with excitation fluence. These can be ascribed to the strong spin\u2013orbit coupling (SOC) demonstrated in FePt and the reduction of transient magnetic anisotropy, respectively. Surprisingly, the demagnetization time exhibits no discernible correlation with ambient temperature. Two competitive factors are proposed to account for this phenomenon. On the other hand, the spin\u2013lattice relaxation accelerates as temperature decreases due to enhanced SOC at lower ambient temperature. A semiquantitative analysis is given to get a visualized understanding. These results offer a comprehensive understanding of the dynamic characteristics of ultrafast demagnetization and recovery processes in iron-based materials with strong SOC, highlighting the potential for regulating the magnetization recovery process through temperature and laser fluence adjustments.<\/jats:p>","DOI":"10.3390\/ma16145086","type":"journal-article","created":{"date-parts":[[2023,7,19]],"date-time":"2023-07-19T21:21:46Z","timestamp":1689801706000},"page":"5086","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Fluence and Temperature Dependences of Laser-Induced Ultrafast Demagnetization and Recovery Dynamics in L10-FePt Thin Film"],"prefix":"10.3390","volume":"16","author":[{"given":"Zhikun","family":"Xie","sequence":"first","affiliation":[{"name":"School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China"},{"name":"State-Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-Sen University, Guangzhou 510275, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuanhai","family":"Cai","sequence":"additional","affiliation":[{"name":"School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Meng","family":"Tang","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jielin","family":"Zhou","sequence":"additional","affiliation":[{"name":"School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Junhao","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Jun","family":"Peng","sequence":"additional","affiliation":[{"name":"School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5151-6053","authenticated-orcid":false,"given":"Tianran","family":"Jiang","sequence":"additional","affiliation":[{"name":"State-Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-Sen University, Guangzhou 510275, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhong","family":"Shi","sequence":"additional","affiliation":[{"name":"Shanghai Key Laboratory of Special Artificial Microstructure Materials and Technology, School of Physics Science and Engineering, Tongji University, Shanghai 200092, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Zhifeng","family":"Chen","sequence":"additional","affiliation":[{"name":"School of Physics and Materials Science, Guangzhou University, Guangzhou 510006, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,19]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"4250","DOI":"10.1103\/PhysRevLett.76.4250","article-title":"Ultrafast spin dynamics in ferromagnetic nickel","volume":"76","author":"Beaurepaire","year":"1996","journal-title":"Phys. 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