{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T01:38:52Z","timestamp":1760060332157,"version":"build-2065373602"},"reference-count":41,"publisher":"MDPI AG","issue":"17","license":[{"start":{"date-parts":[[2025,8,27]],"date-time":"2025-08-27T00:00:00Z","timestamp":1756252800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Key Research and Development Program of China","award":["2023YFF0719200","2022YFB4400200","2024KQ074","12274322","52471254"],"award-info":[{"award-number":["2023YFF0719200","2022YFB4400200","2024KQ074","12274322","52471254"]}]},{"name":"State Key Laboratory of Spintronics in Hangzhou","award":["2023YFF0719200","2022YFB4400200","2024KQ074","12274322","52471254"],"award-info":[{"award-number":["2023YFF0719200","2022YFB4400200","2024KQ074","12274322","52471254"]}]},{"name":"Natural Science Foundation of China","award":["2023YFF0719200","2022YFB4400200","2024KQ074","12274322","52471254"],"award-info":[{"award-number":["2023YFF0719200","2022YFB4400200","2024KQ074","12274322","52471254"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>The interfacial Dzyaloshinskii\u2013Moriya interaction (DMI) plays a pivotal role in stabilising and controlling the motion of chiral spin textures, such as N\u00e9el-type bubble domains, in ultrathin magnetic films\u2014an essential feature for next-generation spintronic devices. In this work, we investigate domain wall (DW) dynamics in magnetron-sputtered Ta(3 nm)\/Pt(3 nm)\/Co(1 nm)\/RuO2(1 nm) [Ru(1 nm)]\/Pt(3 nm) multilayers, benchmarking their behaviour against control stacks. Vibrating sample magnetometry (VSM) was employed to determine saturation magnetisation and perpendicular magnetic anisotropy (PMA), while polar magneto-optical Kerr effect (P-MOKE) measurements provided coercivity data. Kerr microscopy visualised the expansion of bubble-shaped domains under combined perpendicular and in-plane magnetic fields, enabling the extraction of effective DMI fields. Brillouin light scattering (BLS) spectroscopy quantified the asymmetric propagation of spin waves, and micromagnetic simulations corroborated the experimental findings. The Pt\/Co\/RuO2 system exhibits a Dzyaloshinskii\u2013Moriya interaction (DMI) constant of \u22481.08 mJ\/m2, slightly higher than the Pt\/Co\/Ru system (\u22481.03 mJ\/m2) and much higher than the Pt\/Co control (\u22480.23 mJ\/m2). Correspondingly, domain walls in the RuO2-capped films show pronounced velocity asymmetry under in-plane fields, whereas the symmetric Pt\/Co\/Pt shows negligible asymmetry. Despite lower depinning fields in the Ru-capped sample, its domain walls move faster than those in the RuO2-capped sample, indicating reduced pinning. Our results demonstrate that integrating RuO2 significantly alters interfacial spin\u2013orbit interactions.<\/jats:p>","DOI":"10.3390\/ma18174008","type":"journal-article","created":{"date-parts":[[2025,8,28]],"date-time":"2025-08-28T07:43:16Z","timestamp":1756366996000},"page":"4008","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Domain Wall Motion and the Interfacial Dzyaloshinskii\u2013Moriya Interaction in Pt\/Co\/RuO2(Ru) Multilayers"],"prefix":"10.3390","volume":"18","author":[{"given":"Milad","family":"Jalali","sequence":"first","affiliation":[{"name":"School of Physics Science and Engineering, Tongji University, Shanghai 200092, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Kai","family":"Wang","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Spintronics, Hangzhou International Innovation Institute, Beihang University, Hangzhou 311115, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Haoxiang","family":"Xu","sequence":"additional","affiliation":[{"name":"School of Physics Science and Engineering, Tongji University, Shanghai 200092, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8591-4466","authenticated-orcid":false,"given":"Yaowen","family":"Liu","sequence":"additional","affiliation":[{"name":"School of Physics Science and Engineering, Tongji University, Shanghai 200092, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sylvain","family":"Eimer","sequence":"additional","affiliation":[{"name":"National Key Laboratory of Spintronics, Hangzhou International Innovation Institute, Beihang University, Hangzhou 311115, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,8,27]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"241","DOI":"10.1016\/0022-3697(58)90076-3","article-title":"A thermodynamic theory of \u201cweak\u201d ferromagnetism of antiferromagnetics","volume":"4","author":"Dzyaloshinsky","year":"1958","journal-title":"J. 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