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In our previous work, we synthesized a metal/2D material heterointerface consisting of L 1 0 -ordered iron–palladium (FePd) and graphene (Gr) called FePd(001)/Gr. This system has been explored by both experimental measurements and theoretical calculations. In this study, we focus on a heterojunction composed of FePd and multilayer graphene referred to as FePd(001)/ m -Gr/FePd(001), where m represents the number of graphene layers. We perform first-principles calculations to predict their spin-dependent transport properties. The quantitative calculations of spin-resolved conductance and magnetoresistance (MR) ratio (150 %– 200 %) suggest that the proposed structure can function as a magnetic tunnel junction in spintronics applications. We also find that an increase in m not only reduces conductance but also changes transport properties from the tunneling behavior to the graphite π -band-like behavior. Additionally, we investigate the spin-transfer torque-induced magnetization switching behavior of our junction structures using micromagnetic simulations. Furthermore, we examine the impact of lateral displacements (sliding) at the interface and find that the spin transport properties remain robust despite these changes; this is the advantage of two-dimensional material hetero-interfaces over traditional insulating barrier layers such as MgO. [ABSTRACT FROM AUTHOR]

Graphene on L 1 0 -FePd(001), which has been experimentally studied in recent years, is a heterogeneous interface with a significant lattice symmetry mismatch between the honeycomb structure of graphene and tetragonal alloy surface. In this work, we report on the density functional study of its atomic-scale configurations, electronic and magnetic properties, and adsorption mechanism, which have not been well understood in previous experimental studies. We propose various atomic-scale models, including simple nontwisted and low-strain twisted interfaces, and analyze their energetical stability by performing structural optimizations using the van der Waals interactions of both DFT-D2 and optB86b-vdW functionals. The binding energy of the most stable structure reached E B = − 0.22 eV/atom for DFT-D2 (E B = − 0.19 eV/atom for optB86b-vdW). The calculated FePd-graphene spacing distance was approximately 2 Å, which successfully reproduced the experimental value. We also find out characteristic behaviors: the modulation of π -bands, the suppression of the site-dependence of adsorption energy, and the rise of moiré-like corrugated buckling. In addition, our atomic structure is expected to help build low-cost computational models for investigating the physical properties of L 1 0 alloys/two-dimensional interfaces. [ABSTRACT FROM AUTHOR]

Objectives: To investigate who needs a careful postoperative monitoring for prostate cancer (PCa) after holmium laser enucleation of the prostate (HoLEP). We examined characteristics and oncological outcomes of HoLEP‐related PCa. Methods: Patients who underwent HoLEP during 2002–2017 in a Japanese tertiary center were retrospectively analyzed. Patients were divided into non‐PCa, PCa with HoLEP specimen (PCa‐Ope), and PCa diagnosed during follow‐up (PCa‐Post). Outcomes of all HoLEP‐related PCa were monitored. Results: Of the total 758, 60 (7.9%) were diagnosed with PCa from resected specimen of HoLEP and 9 (1.2%) were diagnosed postoperatively. Preoperative prostate‐specific antigen (iPSA), postoperative PSA (pPSA), and PSA density were significantly higher in both PCa groups than those in non‐PCa group. While iPSA significantly correlated to prostate volume (PV), pPSA was not associated with PV. A receiver‐operating‐characteristics curve demonstrated that pPSA 1.2 ng/mL achieved the optimal cut‐off (AUC 0.95) for the incidence of PCa‐Post. In addition to the incidence of PCa and iPSA, lower enucleation efficiency (enucleated volume /PV) was significantly associated with pPSA >1.2 ng/mL. Among PCa‐Ope, 51 were Grade Group (GG) ≤2 and 42 were followed‐up with active surveillance, whereas 8 of 9 PCa‐Post were GG ≥3 and 2 progressed to death. Conclusions: Patients undergoing HoLEP are associated with some risk of potential PCa. While oncological outcomes were favorable among PCa‐Ope, postoperative PSA should be carefully monitored even if not diagnosed with PCa with HoLEP specimen. Enucleation efficiency should be also considered not to misread pPSA value. [ABSTRACT FROM AUTHOR]

A BiFeO3 (BFO) film is epitaxially grown on an (La0.3Sr0.7)(Al0.65Ta0.35)O3 (LSAT) substrate to investigate the lattice mismatch effect on the domain structure and lattice strain status within the BFO film. Atomic resolution scanning transmission electron microscope image, selected area electron diffraction (SAED) patterns, and X-ray reciprocal space mapping (XRSM) data clearly reveal that the lattice strain originating from the lattice mismatch between BFO and LSAT is relaxed by causing misfit dislocations in the BFO film. The SAED and XRSM data indicate that the crystal structure of BFO film is rhombohedral with the space group R3c. In particular, XRSM data acquired along two different in-plane orientations reveal that the BFO layer consists of two different domains that were 90° off each other with respect to the surface normal orientation. An atomistic model based on the crystal orientation relation found by SAED and XRSM shows that (1) the ferroelectric polarization axes of both domains are 35.6° with respect to the BFO film surface and (2) the two domains are consistent with the so-called 71° (and/or 109°) ferroelectric domains reported previously. The lattice mismatch of ∼2.8% calculated based on the epitaxial relation is proposed to be too large to be stored as elastic strain energy within the BFO layer. [ABSTRACT FROM AUTHOR]

The effect of Pb and La contents on the lattice configuration in La-substituted Pb([Zr.sub.0.65],[Ti.sub.0.35])[O.sub.3] (La-PZT) films is examined and La-PZT films with various La and Pb contents are prepared on Pt/Ti/Si[O.sub.2]/Si substrates by chemical solution deposition (CSD). The studies have shown that excess Pd has prevented the A-site substituent of La ions.

The magnetic properties and ferroelectric properties of fabricated BiFe[O.sub.3]-based composite films are discussed. Results suggest the maximum remanent magnetization of approximately 20 emu/[cm.sup.3] and magnetic coercive field of 1.5 kOc.

A chemical solution deposition (CSD) method was used for the fabrication of a multiferroic BiFe[O.sub.3] film on a Pt/Ti/Si[O.sub.2]/Si(100) substrate. Findings reveal the saturation magnetization of less than 1 emu/[cm.sup.3] at room temperature.