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Spin pumping in yttrium-iron-garnet (YIG)/nonmagnetic-metal (NM) layer systems under ferromagnetic resonance (FMR) conditions is a popular method of generating spin current in the NM layer. A good understanding of the spin current source is essential in extracting spin Hall angle of the NM and in potential spintronics applications. It is widely believed that spin current is pumped from precessing YIG magnetization into NM layer. Here, by combining microwave absorption and DC-voltage measurements on thin YIG/Pt and YIG/NM1/NM2 (NM1 = Cu or Al, NM2 = Pt or Ta), we unambiguously showed that spin current in NM, instead of from the precessing YIG magnetization, came from the magnetized NM surface (in contact with thin YIG), either due to the magnetic proximity effect (MPE) or from the inevitable diffused Fe ions from YIG to NM. This conclusion is reached through analyzing the FMR microwave absorption peaks with the DC-voltage peak from the inverse spin Hall effect (ISHE). The voltage signal is attributed to the magnetized NM surface, hardly observed in the conventional FMR experiments, and was greatly amplified when the electrical detection circuit was switched on. [ABSTRACT FROM AUTHOR]

The MnSex (x = 1,2) nanoparticles were synthesized under hydrothermal condition, by reaction of the reduced selenium and Mn2+ ion in the presence of hydrazine and acetic acid. By precisely controlling the pH value of the solution, a series of MnSex particles were synthesized. The structure and morphology of as-prepared particles were examined with x-ray diffractometer (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The average sizes of as-prepared particles varied from nanoscale to microscale with pH value increase. Furthermore, the nucleation and growth mechanism associated with pH values were discussed, which can be applied to the hydrothermal synthesis of metal chalcogenide in general. Finally, the optical and magnetic properties of as-prepared particles were measured. All as-made particles exhibit a ferromagnetic behavior with low coercivity and remanence at room temperature. [ABSTRACT FROM AUTHOR]

We present a new member of the biometrics family—i.e., nose pores—which uses particularly interesting properties of nose pores as a basis for noninvasive biometric assessment. The pore distribution on the nose is stable and easily inspected. More important, nose pore distribution features are distinguishable between different persons. Thus, these features can be used for personal identification. However, little work has been done on nose pores as a biometric identifier. We have developed an end-to-end recognition system based on nose pore features. We also made use of a database of nose pore images obtained over a long period to examine the performance of nose pores as a biometric identifier. This research showed that the nose pore is a promising candidate for biometric identification and deserves further research. The experimental results based on the unique nose pores database demonstrated that nose pores can give an 88.07 correct recognition rate for biometric identification, which showed this biometric identifier’s feasibility and effectiveness. [ABSTRACT FROM AUTHOR]

We performed spin-polarized density functional calculations to study the stable configurations, energetics and electronic structures of Co-doped single-walled silicon nanotubes (CoSi2NTs) with the stoichiometry of CoSi2. We found that the incorporation of Co atoms into the wall of SiNTs not only effectively stabilizes the tubes but also tunes their electronic properties. The formation energies of the CoSi2NTs are much lower than those of pristine SiNTs, indicating the plausibility of these tubes. The electronic structures of the CoSi2NTs display the characters of metals. This provides a promising synthetic route to stable SiNTs which may find potential applications in building nanoscale devices. [ABSTRACT FROM AUTHOR]