{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,10]],"date-time":"2026-04-10T11:08:00Z","timestamp":1775819280348,"version":"3.50.1"},"reference-count":32,"publisher":"MDPI AG","issue":"3","license":[{"start":{"date-parts":[[2025,2,5]],"date-time":"2025-02-05T00:00:00Z","timestamp":1738713600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Materials"],"abstract":"<jats:p>V\/Fe multilayers were prepared on naturally oxidized Si(100) substrates at room temperature (RT) by UHV magnetron sputtering. Mixing effects at the Fe\u2013V interfaces were investigated in-situ, directly after deposition, by means of X-ray photoelectron spectroscopy (XPS). The results of systematic in-situ XPS studies of the integral intensity of the Fe-2p peak, as a function of the nominal thickness of the Fe sublayer deposited on vanadium, allowed us to estimate the thickness of the pure iron layer that forms the mixed layer at about 0.4 nm. Assuming the same thickness of the vanadium layer that forms the mixed layer, the estimated thickness of the mixed layer near the Fe\u2013V interface was about 0.8 nm. In the analysis of magnetic hysteresis loops, in addition to the bilinear (J1) and biquadratic (J2) coupling constant, the contribution of the cubic exchange constant (J3) was taken into account, which also contributed significantly to the total energy. Higher order interactions (J2 and J3) are particularly important for V spacer thicknesses greater than 7 atomic monolayers. Hydrogen absorption in V\/Fe multilayers at RT and a pressure of about 1 bar causes an increase in the biquadratic coupling constant J2, while the values of J1 and J3 are reduced. A comparison of the obtained experimental results and available theoretical models leads to the conclusion that the mechanism of \u201cfluctuating thickness of the non-magnetic spacer\u201d could be responsible for the biquadratic exchange coupling. On the other hand, the \u201cloose spins\u201d model can explain the cubic coupling in the V\/Fe multilayers. The modification of the interlayer exchange coupling using hydrogen is fully reversible.<\/jats:p>","DOI":"10.3390\/ma18030697","type":"journal-article","created":{"date-parts":[[2025,2,5]],"date-time":"2025-02-05T07:44:59Z","timestamp":1738741499000},"page":"697","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":1,"title":["Influence of Interface Mixed Layer on Non-Collinear Exchange Coupling in V-Fe Multilayers"],"prefix":"10.3390","volume":"18","author":[{"given":"Agnieszka","family":"Ranecka","sequence":"first","affiliation":[{"name":"Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-7980-8293","authenticated-orcid":false,"given":"Maria","family":"Pugaczowa-Michalska","sequence":"additional","affiliation":[{"name":"Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6174-8694","authenticated-orcid":false,"given":"Les\u0142aw","family":"Smardz","sequence":"additional","affiliation":[{"name":"Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, 60-179 Pozna\u0144, Poland"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2025,2,5]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Ellis, M.O.A., Ababei, R.-V., Wood, R., Evans, R.F.L., and Chantrell, R.W. (2017). Manifestation of higher-order inter-granular exchange in magnetic recording media. Appl. Phys. Lett., 111.","DOI":"10.1063\/1.4990604"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"1531","DOI":"10.1103\/RevModPhys.80.1531","article-title":"Nobel Lecture: From spin waves to giant magnetoresistance and beyond","volume":"80","year":"2008","journal-title":"Rev. Mod. Phys."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"1517","DOI":"10.1103\/RevModPhys.80.1517","article-title":"Nobel Lecture: Origin, development, and future of spintronics","volume":"80","author":"Fert","year":"2008","journal-title":"Rev. Mod. Phys."},{"key":"ref_4","doi-asserted-by":"crossref","unstructured":"Barna\u015b, J., Fuss, A., Camley, R.E., Gr\u00fcnberg, P., and Zinn, W. (1990). Novel magnetoresistance effect in layered magnetic structures: Theory and experiment. Phys. Rev. B, 42.","DOI":"10.1103\/PhysRevB.42.8110"},{"key":"ref_5","doi-asserted-by":"crossref","unstructured":"Tsymbal, E.Y., and Pettifor, D.G. (2001). Perspectives of giant magnetoresistance. Solid State Phys., 56.","DOI":"10.1016\/S0081-1947(01)80019-9"},{"key":"ref_6","unstructured":"O\u2019Handley, R.C. (2000). Modern Magnetic Materials: Principles and Applications, John Wiley & Sons, Inc."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"261","DOI":"10.1103\/PhysRevB.46.261","article-title":"Ruderman\u2014Kittel theory of oscillatory interlayer exchange coupling","volume":"46","author":"Bruno","year":"1992","journal-title":"Phys. Rev. B"},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"844","DOI":"10.1103\/PhysRevLett.69.844","article-title":"Quantum well states as mediators of magnetic coupling in superlattices","volume":"69","author":"Ortega","year":"1992","journal-title":"Phys. Rev. Lett."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"901","DOI":"10.1103\/PhysRevLett.79.901","article-title":"Reversible Tuning of the Magnetic Exchange Coupling in Fe\/V (001) Superlattices Using Hydrogen","volume":"79","author":"Dura","year":"1997","journal-title":"Phys. Rev. Lett."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"3252","DOI":"10.1103\/PhysRevLett.68.3252","article-title":"Magnetoresistivity and oscillatory interlayer magnetic coupling of sputtered Fe\/Nb superlattices","volume":"68","author":"Mattson","year":"1992","journal-title":"Phys. Rev. Lett."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"1150","DOI":"10.1103\/PhysRevLett.78.1150","article-title":"Continuous and Reversible Change of the Magnetic Coupling in an Fe\/Nb Multilayer Induced by Hydrogen Charging","volume":"78","author":"Klose","year":"1997","journal-title":"Phys. Rev. Lett."},{"key":"ref_12","unstructured":"Stiles, M. (2002). Interlayer Exchange Coupling in Ultrathin Magnetic Structures, Spinger."},{"key":"ref_13","doi-asserted-by":"crossref","unstructured":"Bruno, P. (2002). Interlayer exchange interactions in magnetic multilayers. Magnetism: Molecules to Materials, Wiley-VCH Verlag GmbH.","DOI":"10.1002\/3527600140.ch9"},{"key":"ref_14","doi-asserted-by":"crossref","unstructured":"Barna\u015b, J. (1992). Coupling between two ferromagnetic films through a non-magnetic metallic layer. J. Magn. Magn. Mater., 111.","DOI":"10.1016\/0304-8853(92)91077-7"},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Barna\u015b, J. (1993). Intrinsic biquadratic contribution to interlayer coupling in magnetic layered structures. J. Magn. Magn. Mater., 123.","DOI":"10.1016\/0304-8853(93)90007-O"},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"3172","DOI":"10.1103\/PhysRevLett.67.3172","article-title":"Fluctuation Mechanism for Biquadratic Exchange Coupling in Magnetic Multilayers","volume":"67","author":"Slonczewski","year":"1991","journal-title":"Phys. Rev. Lett."},{"key":"ref_17","doi-asserted-by":"crossref","unstructured":"Slonczewski, J.C. (1993). Origin of biquadratic exchange in magnetic multilayers (invited). J. Appl. Phys., 73.","DOI":"10.1063\/1.353483"},{"key":"ref_18","doi-asserted-by":"crossref","unstructured":"Slonczewski, J.C. (1995). Overview of interlayer exchange theory. J. Magn. Magn. Mater., 150.","DOI":"10.1016\/0304-8853(95)00081-X"},{"key":"ref_19","doi-asserted-by":"crossref","unstructured":"Sch\u00e4fer, M., Demokritov, S., M\u00fcller-Pfeiffer, S., Sch\u00e4fer, R., Schneider, M., Gr\u00fcnberg, P., and Zinn, W. (1995). Investigation of 90\u00b0 coupling in Fe\/Ag\/Fe structures: \u2018\u2018Loose spins\u2019\u2019 and fluctuation mechanism. J. Appl. Phys., 77.","DOI":"10.1063\/1.359117"},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"151","DOI":"10.1016\/S0921-4526(03)00284-9","article-title":"Polarized neutron and X-ray reflectivity study of the structure and exchange coupling of permalloy(Ni80Fe20)\/Cr\/permalloy trilayers","volume":"336","author":"Yu","year":"2003","journal-title":"Phys. B"},{"key":"ref_21","doi-asserted-by":"crossref","unstructured":"Zhang, Y., Li, X., Zhang, Y., Liu, J., Dai, B., and Ren, Y. (2024). The effect of roughness in reverse magnetization process of [Co\/Cu]2 multilayers. Appl. Phys. A, 130.","DOI":"10.1007\/s00339-023-07273-x"},{"key":"ref_22","doi-asserted-by":"crossref","unstructured":"Marczy\u0144ska, A., Skoryna, J., Szyma\u0144ski, B., and Smardz, L. (2015). Growth and structural characterisation of V\/Fe multilayers. Acta Phys. Pol. A, 127.","DOI":"10.12693\/APhysPolA.127.552"},{"key":"ref_23","doi-asserted-by":"crossref","unstructured":"Marczy\u0144ska, A., Synoradzki, K., Pugaczowa-Michalska, M., Toli\u0144ski, T., and Smardz, L. (2018). Interlayer exchange coupling and proximity effect in V-Fe multilayers. Acta Phys. Pol. A, 133.","DOI":"10.12693\/APhysPolA.133.597"},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"806","DOI":"10.1016\/j.ijhydene.2020.09.175","article-title":"Interface mixing and hydrogen absorption in Pd\/Mg and Pd\/Al\/Mg thin films","volume":"46","author":"Pacanowski","year":"2021","journal-title":"Int. J. Hydrogen Energy"},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"17953","DOI":"10.1103\/PhysRevB.50.17953","article-title":"Projector augmented-wave method","volume":"50","author":"Blochl","year":"1994","journal-title":"Phys. Rev. B"},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"1758","DOI":"10.1103\/PhysRevB.59.1758","article-title":"From ultrasoft pseudopotentials to the projector augmented-wave method","volume":"59","author":"Kresse","year":"1999","journal-title":"Phys. Rev. B"},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"11169","DOI":"10.1103\/PhysRevB.54.11169","article-title":"Efficient iterative schemes for ab initio total-energy calculations using a plane-wave basis set","volume":"54","author":"Kresse","year":"1996","journal-title":"Phys. Rev. B"},{"key":"ref_28","doi-asserted-by":"crossref","first-page":"3865","DOI":"10.1103\/PhysRevLett.77.3865","article-title":"Generalized Gradient Approximation Made Simple","volume":"77","author":"Perdew","year":"1996","journal-title":"Phys. Rev. Lett."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"26840","DOI":"10.1016\/j.ijhydene.2023.03.282","article-title":"Influence of Ni interlayer on hydrogen absorption and cyclicity in Gd thin films","volume":"48","author":"Wachowiak","year":"2023","journal-title":"Int. J. Hydrogen Energy"},{"key":"ref_30","doi-asserted-by":"crossref","unstructured":"Wachowiak, M., and Smardz, L. (2023). Effect of interfacial mixed layer on hydrogen absorption in yttrium thin films. J. Alloys Compd., 941.","DOI":"10.1016\/j.jallcom.2023.168974"},{"key":"ref_31","unstructured":"Briggs, D. (1977). Handbook of X-Ray and Ultraviolet Photoelectron Spectroscopy, Heyden & Son Ltd."},{"key":"ref_32","doi-asserted-by":"crossref","unstructured":"Ahlberg, M., Papaioannou, E., Nowak, G., and Hj\u00f6rvarsson, B. (2013). Temperature dependence of magnetic properties in weakly exchange coupled Fe\/V superlattices. J. Magn. Magn. Mater., 341.","DOI":"10.1016\/j.jmmm.2013.04.058"}],"container-title":["Materials"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/3\/697\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,9]],"date-time":"2025-10-09T16:27:19Z","timestamp":1760027239000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1996-1944\/18\/3\/697"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2025,2,5]]},"references-count":32,"journal-issue":{"issue":"3","published-online":{"date-parts":[[2025,2]]}},"alternative-id":["ma18030697"],"URL":"https:\/\/doi.org\/10.3390\/ma18030697","relation":{},"ISSN":["1996-1944"],"issn-type":[{"value":"1996-1944","type":"electronic"}],"subject":[],"published":{"date-parts":[[2025,2,5]]}}}