Research Article Local structure and magnetic properties of a nanocrystalline Mnrich Cantor alloy thin film down to the atomic scale  

作　　者：Alevtina Smekhova Alexei Kuzmin Konrad Siemensmeyer Chen Luo James Taylor Sangeeta Thakur Florin Radu Eugen Weschke Ana Guilherme Buzanich Bin Xiao Alan Savan Kirill V.Yusenko Alfred Ludwig 

机构地区：[1]Helmholtz-Zentrum Berlin für Materialien und Energie(HZB),Berlin D-12489,Germany [2]Institute of Solid State Physics,University of Latvia,Riga LV-1063,Latvia [3]Physik-Department,Technische Universität München,Garching D-85748,Germany [4]Institut für Experimentalphysik,Freie Universität Berlin,Berlin 14195,Germany [5]Bundesanstalt für Materialforschung und-prüfung(BAM),Berlin D-12489,Germany [6]Institut für Werkstoffe,Ruhr-Universität Bochum,Bochum D-44801,Germany

出　　处：《Nano Research》2023年第4期5626-5639,共14页纳米研究（英文版）

摘　　要：The huge atomic heterogeneity of high-entropy materials along with a possibility to unravel the behavior of individual components at the atomic scale suggests a great promise in designing new compositionally complex systems with the desired multifunctionality.Herein,we apply multi-edge X-ray absorption spectroscopy(extended X-ray absorption fine structure(EXAFS),Xray absorption near edge structure(XANES),and X-ray magnetic circular dichroism(XMCD))to probe the structural,electronic,and magnetic properties of all individual constituents in the single-phase face-centered cubic(fcc)-structured nanocrystalline thin film of Cr_(20)Mn_(26)Fe_(18)Co_(19)Ni_(17)(at.%)high-entropy alloy on the local scale.The local crystallographic ordering and componentdependent lattice displacements were explored within the reverse Monte Carlo approach applied to EXAFS spectra collected at the K absorption edges of several constituents at room temperature.A homogeneous short-range fcc atomic environment around the absorbers of each type with very similar statistically averaged interatomic distances(2.54-2.55Å)to their nearest-neighbors and enlarged structural relaxations of Cr atoms were revealed.XANES and XMCD spectra collected at the L2,3 absorption edges of all principal components at low temperature from the oxidized and in situ cleaned surfaces were used to probe the oxidation states,the changes in the electronic structure,and magnetic behavior of all constituents at the surface and in the sub-surface volume of the film.The spin and orbital magnetic moments of Fe,Co,and Ni components were quantitatively evaluated.The presence of magnetic phase transitions and the co-existence of different magnetic phases were uncovered by conventional magnetometry in a broad temperature range.

关 键 词：high-entropy alloys reverse Monte Carlo(RMC) element-specific spectroscopy extended X-ray absorption fine structure(EXAFS) X-ray magnetic circular dichroism(XMCD) MAGNETISM 

分 类 号：TB383[一般工业技术—材料科学与工程]