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The sputtering rate of Pt, Au, Fe and Co targets was researched and they were 0.059 nm/s, 0.076 nm/s, 0.050 nm/s, and 0.030nm/s respectively. A series of magnetic multilayers were prepared using the calibrated rate and the anomalous hall effect of the samples were tested, and Hall curve was in line with expectations. The sputtering rate of Pt, Au, Fe and Co targets was appropriate for sample preparation. Suitable sputtering rate play a decisive role in sample preparation.

Two-dimensional (2D) InSe and WS2 exhibit promising characteristics for optoelectronic applications. However, they both have poor absorption of visible light due to wide bandgaps: 2D InSe has high electron mobility but low hole mobility, while 2D WS2 is on the contrary. We propose a 2D heterostructure composed of their monolayers as a solution to both problems. Our first-principles calculations show that the heterostructure has a type-II band alignment as expected. Consequently, the bandgap of the heterostructure is reduced to 2.19 eV, which is much smaller than those of the monolayers. The reduction in bandgap leads to a considerable enhancement of the visible-light absorption, such as about fivefold (threefold) increase in comparison to monolayer InSe (WS2) at the wavelength of 490 nm. Meanwhile, the type-II band alignment also facilitates the spatial separation of photogenerated electron-hole pairs; i.e., electrons (holes) reside preferably in the InSe (WS2) layer. As a result, the two layers complement each other in carrier mobilities of the heterostructure: the photogenerated electrons and holes inherit the large mobilities from the InSe and WS2 monolayers, respectively.

An analytic method is proposed to calculate the formation enthalpy directly from empirical n-body potential and applied to the binary and ternary systems consisting of the refractory metals Mo, Nb, Ta and W. It turns out that the calculated enthalpies are in overall agreement with experimental observations and some other theoretical calculations. Interestingly, it shows that the formation enthalpies of the ternary systems are significantly affected by those of the constituent binary systems.

The self-consistent electronic structure calculations were carried out with the accurate frozen-core full-potential projector augmented-wave method on 13 Ni-Pt intermetallic compounds of simple crystalline structures, i.e. A15, D019, D03 and L12 Ni3Pt and NiPt3, and α-NiAs, B1, B2, L2a, and L10 NiPt. The calculations reveal that the L12 Ni3Pt, L10 NiPt and L12 NiPt3 are energetically more stable than their respective competitive structures, indicating that the three structures may be formed in some appropriate conditions. The obtained results match well with the experimental observation or other theory predictions. It is found that there is hybridization between Ni 3d and Pt 5d states, which may significantly affect the structural stability and magnetism of metastable Ni-Pt intermetallic compounds.

An n-body Ni–Nb–Ta potential is constructed to conduct molecular dynamics simulations using 129 solid solution models with various compositions. Comparing the relative stability of solid solutions versus their disordered counterparts, simulations determine two critical solid-solubility lines, which define a region in the composition triangle. If an alloy is located inside the defined region, a disordered state is energetically favored; if it is located outside, a crystalline solid solution is preserved. The region is therefore named as the metallic glass-forming region.

Based on the projector augmented-wave method, ab initio calculations are performed for 20 representative binary Ni–Au, Ni–Cu, Ni–Zn, and Ni–Al alloys at A 3 B composition. The calculations reveal that the D0 22 Ni 3 Au, Ni 3 Cu, Ni 3 Zn, and L1 2 Ni 3 Al are more energetically stable than their respective competitive structures, indicating that the four structures may be formed in some appropriate conditions. The calculations indicate that different structures have small effects on the magnetic moments for Ni 3 Au and Ni 3 Cu alloys, while have large effects on the magnetic moments for Ni 3 Zn and Ni 3 Al alloys. It is also predicted that there is strong hybridization between Ni 3d and Cu 3d states in Ni 3 Cu and Ni 3d and Au 5d states in Ni 3 Au alloys and little hybridization in Ni 3 Al and Ni 3 Zn, which may significantly affect on structural stability and magnetism of these structures. The calculations suggest that the magnetism may increase the energetic stability of these structures. It is hoped tha...