Pseudo-Hall effect and anisotropic magnetoresistance in a micronscale Ni80Fe20 device

The pseudo-Hall effect (PHE) and anisotropic magnetoresistance (AMR) in a micronscale Ni80Fe20, six-terminal device, fabricated by optical lithography and wet chemical etching from a high quality UHV grown 30 Angstrom Au/300 Angstrom Ni80Fe20 film, have been studied. The magnetisation reversal in different parts of the device has been measured using magneto-optical Kerr effect (MOKE), The device gives a 50% change in PHE voltage with an ultrahigh sensitivity of 7.3%Oe(-1) at room temperature. The correlation between the magnetisation, magneto-transport properties, lateral shape of the device and directions of the external applied field is discussed based on extensive MOKE, AMR and PHE results

Influence of lateral geometry on magnetoresistance and magnetisation reversal in Ni80Fe20 wires

The magnetisation reversal processes and magnetoresistance behaviour in micron-sized Ni80Fe20 wires with triangular and rectangular modulated width have been studied. The wires were fabricated by electron beam lithography and a lift-off process. A combination of magnetic force microscopy (MFM), magneto-optical Kerr effect (MOKE) and magnetoresistance (MR) measurements shows that the lateral geometry of the wires greatly influences the magnetic and transport properties. The width modulations modify not only the shape-dependent demagnetising fields, but also the current density. The correlation between the lateral geometry, the magnetic and the transport properties is discussed based on MFM, MOKE and MR results

The COVID-19 Pandemic: Public Health and Epidemiology

In this issue of the journal, we publish a review of COVID-19 infection by 2 eminent virologists, MacKenzie and Smith (see in this issue). It is too early in the history of the COVID-19 outbreak to write the full history, but their article provides a good outline of the emerging pandemic. The disease is causing widespread social disruption in many countries, and it has just been announced that the 2020 Asia Pacific Academic Consortium for Public Health (APACPH) Conference has been postponed indefinitely..

How Loneliness Affects Problematic Facebook Use

The main objective of this paper is to show how loneliness affects problematic Facebook use. We integrated the concept of loneliness in the advanced cognitive-behavioral model of generalized problematic Internet use and empirically tested the model with 200 Facebook users. Our findings suggested that loneliness predisposes individuals to the development of problematic Facebook use and confirmed that the preference for online social interaction and mood regulation predict deficient self-regulation of Facebook use and which in turn leads to negative outcomes

Magnetic domain evolution in permalloy mesoscopic dots

Permalloy (Ni80Fe20) squares (30 nm thick and w mu m wide; 1 less than or equal to w less than or equal to 200 mu m) and circular disks (30 nm thick and r mu m diameter; 1 less than or equal to r less than or equal to 200 mu m) prepared on a GaAs (100) substrate were observed in both their demagnetized and remanent states by magnetic force microscopy (MFM) associated with non-contact atomic force microscopy (NC-AFM). The squares (2 less than or equal to w mu m) exhibited conventional closure domains and the corner plays a very important role in creating new walls. The circular disks, on the other hand, formed either vortex domain (5 less than or equal to r less than or equal to 20 mu m) or multi-domain (50 less than or equal to r mu m) states, The magnetization rotation is observed by MFM to change according to the size and shape of the elements, The MFM observations are supported by micromagnetic calculations which confirm the effect of the corner on the domain wall formation

Microstructure and properties of multiphase and functionally graded materials prepared by chemical vapor deposition

The synthesis of multiphase and functionally graded materials by chemical vapor deposition is discussed from a perspective of controlling their composition and microstructure at a nano-scale level, and ultimately, tailoring their material properties. Prior research is briefly reviewed to address the current state of this novel material concept. Recent experimental results relating to controlling the selected properties of two multiphase systems, TiN + MoS{sub 2} and NiAl + Al{sub 2}O{sub 3}, are described to illustrate this concept`s potential merits and challenges for use in realistic applications

Magnetization reversal in mesoscopic Ni80Fe20 wires: A magnetic domain launching device

The magnetization reversal process in mesoscopic permalloy (Ni80Fe20) wire structures has been investigated using scanning Kerr microscopy, magnetic force microscopy (MFM) and micromagnetic calculations. We find that the junction offers a site for reversed domain wall nucleation in the narrow part of the wires. As a consequence, the switching field is dominated by the domain nucleation field and the junction region initiates reversal by the wall motion following the nucleation of domains. Our results suggest the possibility of designing structures that can be used to “launch” reverse domains in narrow wires within a controlled field rang

Ferromagnetic/III-V semiconductor heterostructures and magneto-electronic devices

The interface magnetic and electronic properties of two Fe/III-V semiconductor systems, namely Fe/GaAs and Fe/InAs, grown at room temperature have been studied. A "magnetic interface", which is essential for the fabrication of magneto-electronic (ME) devices, was realized in both Fe/GaAs and Fe/InAs systems with suitable substrate processing and growth conditions. Furthermore, Fe/InAs was shown to have favorable interface electronic properties as Fe forms a low resistance ohmic contact on InAs. Two prototypes of ME device based on Fe/InAs are also discussed

Magnetization reversal and magnetic anisotropy in Co network nanostructures

The magnetization reversal and magnetic anisotropy in Co network structures have been studied using magneto-optic Kerr effect (MOKE). An enhancement of the coercivity is observed in the network structures and is attributed to the pinning of domain walls by the hole edges in the vicinity of which the demagnetizing field spatially varies. We find that the magnetization reversal process is dominated by the intrinsic unaxial anisotropy (2K(u)/M(s)approximate to 200 Oe) in spite of the shape anisotropy induced by the hole edges. The influence of the cross-junction on the competition between the intrinsic uniaxial anisotropy and the induced shape anisotropy is discussed using micromagnetic simulations

LOMA: A fast method to generate efficient tagged-random primers despite amplification bias of random PCR on pathogens

10.1186/1471-2105-9-368BMC Bioinformatics9BBMI