Magnetic properties and microstructure of vapour-deposited Fe/Hf films upon thermal annealing

Abstract

Fe/Hf multilayers were prepared by alternate deposition of pure hafnium and iron. As-deposited samples were then annealed at 380 °C and 550 °C, respectively, to investigate the microstructure and magnetic property changes of the films. It was found that all as-deposited Fe/Hf films exhibited the soft ferromagnetic property where the coercive force was lower than 30 Oe. The coercive force and the magnetic moment per Fe atom changed significantly with the annealing temperature and the Fe layer thickness (tFe ). For tFe = 2.2-4.2 nm films, their soft ferromagnetic properties were stable upon thermal annealing at 380 and 550 °C, while for tFe 9.5 nm and tHf = 13.2 nm films, after annealing at 550 °C for 20 min, as-deposited films transformed from having a soft ferromagnetic property to having a hard ferromagnetic one. The residual magnetization and maximum magnetic energy product of the films could come up to about 0.81 µB and 8.8 kJ m-3 (1.1 MGOe), for the Fe(9.5 nm)/Hf(13.2 nm) films annealed at 550 °C. It was also found that there were two metastable phases with fcc structure in the annealed Fe-Hf films. The magnetic change mechanism was discussed in terms of interdiffusion in the Fe/Hf interface and phase transformation in the films upon thermal annealing.

Magnetic properties of mechanically alloyed Fe100−xZrx(20 ⩽x⩽ 35) powder

“…The obtained value of high-field susceptibility is small (figure 6(b)) and has a magnitude of 10 −7 , suggesting that only a small number of spins have the same orientation in a given domain. These observations are consistent with a non-collinear spin arrangement arising due to the co-existence of finite topological disorder (resulting from the MA process) and frustration of magnetic interaction (resulting from the change in the Fe-Fe atomic distance with Zr concentration) [37]. The coefficients of the higher order terms are small and contribute only to a minor deviation of the magnetization curves in the measured range of the magnetic field.…”

Single-Cell Analysis Differentiates the Effects of p53 Mutation and p53 Loss on Cell Compositions of Oncogenic Kras-Driven Pancreatic Cancer

“…Previous studies have shown that both gain-of-function or loss-of-function types of p53 mutations can occur in human pancreatic cancer and have distinct impacts on tumor progression [15,16]. Oncogenic effects are often observed in the gain-of-function p53 mutations, which are commonly found in R175H, R248Q, R248W, R273C, R273H, G245S, H179R, Y163C, Y220C, Y234C, G249, and R282 [19,20]. On the other hand, loss-of-function p53 mutations are associated with increased tumor penetrance and decreased life expectancy, as seen in the context of the p53 E224D mutant [40].…”

“…We obtained TCGA data of a pancreatic cancer cohort from the cBioPortal database and identified cases with TP53 truncating mutations as p53 loss (loss-of-function) in the context of KRAS G12* mutations. In comparison, we also identified cases with TP53 mutations including R175H, R248Q, R248W, R273C, R273H, G245S, H179R, Y163C, Y220C, Y234C, G249, and R282 as p53 gain-of-function mutations [19,20] in the context of the KRAS G12* mutations. We then compared the mRNA expression levels of selected genes between p53 loss and p53 mutation groups.…”

“…The p53 R172H mutation has been shown to be associated with p53 gain of function and overexpression in cancer cells, leading to oncogenic effects [15][16][17][18]. The other commonly observed p53 mutations in human cancers include R248Q, R248W, R273C, R273H, G245S, H179R, Y163C, Y220C, Cells 2023, 12, 2614 2 of 20 Y234C, G249, and R282, which are associated with p53 gain-of-function mutations [19][20][21]. Recent studies reported that p53 R248W can promote the metastasis of human pancreatic cancer [22].…”

Structural-elastic relationships of Zr-TL (TL = Cu, Co, Ni) thin films metallic glasses

“…Since the metallic glasses were first discovered in 1960 [1], researchers are interested in their unique atomic packing structures [2] mechanical [3], electronic [4], and magnetic [5] properties. The initial limitation in preparing bulk metallic glasses (BMGs) by rapid quench techniques was gradually overcome by coupling appropriate elements with different atomic sizes based on the empirical rules pointed out by Inoue [6].…”