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Hall transport and non-collinear magnetoresistance (NCMR) are studied for a chiral antiferromagnet (AFM) with the filled β-Mn-type structure. Magnetic and transport properties of epitaxial thin films of Co2−xPdxMo3N revealed that, in addition to a canted antiferromagnetic behavior above room temperature, thin films with x = 1.01∼1.38 exhibited a transition to a spin spiral state with a higher magnetic moment below TSR of around 50 K, which was assigned to a spin reorientation transition. The low-temperature phase shows both large anomalous Hall effect (AHE) and topological Hall effect (THE). Upon the transition to the canted AFM phase existing up to room temperature, the large AHE still persists with vanishing THE. The behavior of the Hall transport properties coupled with NCMR signals in the current-perpendicular-to-the plane configuration shows the formation of topological spin textures with locally antiferromagnetic order. The present results open the way for the study of topological antiferromagnetic spin textures, manipulation of their properties, and for future spintronic applications. [ABSTRACT FROM AUTHOR]

Magnetically soft Fe-Co alloy cluster-assembled films were produced at room temperature by an energetic cluster deposition. Size-monodispersed Fe-Co alloy clusters whose average sizes ranged between 8 and 14 nm were obtained using a plasma-gas-condensation-type cluster deposition apparatus. Positively charged clusters in a cluster beam were accelerated electrically and deposited onto a negatively biased substrate together with neutral clusters from the same cluster source, leading to formation of high-density Fe-Co alloy cluster-assembled films. Magnetic properties were observed for these films prepared by changing the bias voltage. Based on the temperature dependence of magnetic coercivity, we estimated the effective magnetic anisotropy constant, Keff, and magnetic exchange length Lex (or Dex) as a function of the packing fraction in the Fe-Co cluster-assembled films: Keff decreases and Lex (or Dex) increases dramatically with the packing fraction. [ABSTRACT FROM AUTHOR]

Erratum: "Magnetic and transport properties of chiral antiferromagnetic Co2-xPdxMo3N thin films" [AIP Adv. 13, 025138 (2023)] There are some text errors in the original article.[1] On page 3, second paragraph, " cm" is corrected as " cm." W. Qiang, T. Fukasawa, T. Hajiri, T. Ito, T. Hihara, and H. Asano, "Magnetic and transport properties of chiral antiferromagnetic Co2-xPdxMo3N thin films", AIP Adv. 13(2), 025138 (2023). [Extracted from the article]

The magnetic, electrical and optical properties of nanoparticle systems often depend on the size and size distribution of nanoparticles. In order to optimize those properties of nanoparticle-assembled materials, only varying the mean size of nanoparticles was not enough, and narrowing the size distribution was also of immense importance. In this study, uniform-sized Fe nanoparticles with different diameters were prepared using a magnetron sputtering combined with inert gas condensation technique. The size and morphology of nanoparticles were observed by transmission electron microscopy (TEM). The statistic results revealed that the size of Fe nanoparticles increased with increasing the flow rate of Ar gas, but a reverse trend was observed when increasing the flow rate of He gas. By adjusting the flow rate of Ar and He gases, uniform-sized Fe nanoparticles with diameter ranging from 6 to 13 nm were obtained. Moreover, the size effects on the electrical and magnetic properties of Fe nanoparticle-assembled films with thickness of about 500 nm were also investigated. The magnetic properties showed that the coercivity increased with increasing the nanoparticle size. The in-situ resistance measurement results of Fe nanoparticle assembled-films also showed a size-dependent behavior. [ABSTRACT FROM AUTHOR]

The compound FeN clusters with cluster sizes of d=8–25 nm were synthesized using a plasma-gas-condensation (PGC) cluster deposition apparatus with changing the nitrogen gas flow rate RN2, and their crystal structures and magnetic properties were investigated. The fcc single-phase FeN clusters which have a tetrahedron shape are obtained, and their lattice parameter is a=0.428 nm, being close to that (a=0.433 nm) of ZnS-type FeN films but clearly different from that (a=0.457 nm) of NaCl-type FeN films. The magnetic measurement results indicate that the present ZnS-type FeN clusters are non-magnetic. The characteristic cusp at Tf=8 K on the zero field cooling (ZFC) thermomagnetic curve is attributed to superparamagnetic behavior of Fe-oxide layer crystallites formed on the FeN cluster surfaces. [Copyright &y& Elsevier]

We studied structure and magnetic properties of FexPt1-x alloy clusters fabricated by a plasma-gas-condensation technique which employs two separate elemental sputtering sources and a growth chamber. Fe and Pt metal vapors generated were cooled rapidly in an Ar atmosphere, and grown into alloy clusters. Most of the as-deposited FexPt1-x alloy clusters are multiply twinned and have predominantly an icosahedral structure. The experimental results also show that there is a narrow distribution of the chemical composition among individual clusters but the Fe and Pt atoms are distributed homogeneously in as-deposited alloy clusters, which is discussed on the basis of a formation process of the alloy clusters in the inert gas-condensation process. The optimal magnetic hardening or the chemically ordered FCT FePt clusters can be achieved at proper annealing temperature for very short annealing time. [Copyright &y& Elsevier]

Indium-tin oxide (ITO)-Fe-cluster composite films were fabricated by plasma-gas-condensation-type cluster beam deposition and RF helicon sputtering method, and the structural, optical, electrical and magnetic properties of the films were investigated. The optical transmittance of about 90% is obtained for the Fe cluster layer thickness of 10 nm although it is decreased with increasing the cluster layer thickness. The resistivity is further decreased by embedding metalic Fe clusters into ITO matrix and a resistivity value of about an order of 10-4Ω cm was obtained. Moreover, the ITO-Fe cluster composite films show ferromagnetism at room temperature even for a cluster layer thickness of 10 nm. [ABSTRACT FROM AUTHOR]

High-density Fe cluster-assembled films were produced at room temperature by an energetic cluster deposition. Though cluster-assemblies are usually sooty and porous, the present Fe cluster-assembled films are lustrous and dense, revealing a soft magnetic behavior. Size-monodispersed Fe clusters with the mean cluster size d=9 nm were synthesized using a plasma-gas-condensation technique. Ionized clusters are accelerated electrically and deposited onto the substrate together with neutral clusters from the same cluster source. Packing fraction and saturation magnetic flux density increase rapidly and magnetic coercivity decreases remarkably with increasing acceleration voltage. The Fe cluster-assembled film obtained at the acceleration voltage of -20 kV has a packing fraction of 0.86±0.03, saturation magnetic flux density of 1.78±0.05 Wb/m2, and coercivity value smaller than 80 A/m. The resistivity at room temperature is ten times larger than that of bulk Fe metal. [ABSTRACT FROM AUTHOR]