70 research outputs found
Postpandemic Conferences: The DATE 2023 Experience
Date is a leading international event providing unique networking opportunities. The conference brings together designers and design automation users, researchers, and vendors, as well as specialists in hardware and software design, testing, and manufacturing of electronic circuits and systems—from system-level hardware and software implementation down to integrated circuit design
Domain wall displacement in Py square ring for single nanometric magnetic bead detection
A new approach based on the domain wall displacement in confined
ferromagnetic nanostructures for attracting and sensing a single nanometric
magnetic particles is presented. We modeled and experimentally demonstrated the
viability of the approach using an anisotropic magnetoresistance device made by
a micron-size square ring of Permalloy designed for application in magnetic
storage. This detection concept can be suitable to biomolecular recognition,
and in particular to single molecule detection.Comment: 8pages, 3figure
Enhanced magnetic moment and conductive behavior in NiFe2O4 spinel ultrathin films
Bulk NiFe2O4 is an insulating ferrimagnet. Here, we report on the epitaxial
growth of spinel NiFe2O4 ultrathin films onto SrTiO3 single-crystals. We will
show that - under appropriate growth conditions - epitaxial stabilization leads
to the formation of a spinel phase with magnetic and electrical properties that
radically differ from those of the bulk material : an enhanced magnetic moment
(Ms) - about 250% larger - and a metallic character. A systematic study of the
thickness dependence of Ms allows to conclude that its enhanced value is due to
an anomalous distribution of the Fe and Ni cations among the A and B sites of
the spinel structure resulting from the off-equilibrium growth conditions and
to interface effects. The relevance of these findings for spinel- and, more
generally, oxide-based heterostructures is discussed. We will argue that this
novel material could be an alternative ferromagetic-metallic electrode in
magnetic tunnel junctions.Comment: accepted for publication in Phys. Rev.
Towards an on-chip platform for the controlled application of forces via magnetic particles: A novel device for mechanobiology
In-vitro tests and analyses are of fundamental importance for investigating biological mechanisms in
cells and bio-molecules. The controlled application of forces to activate specific bio-pathways and
investigate their effects, mimicking the role of the cellular environment, is becoming a prominent
approach in this field. In this work, we present a non-invasive magnetic on-chip platform which allows
for the manipulation of magnetic particles, through micrometric magnetic conduits of Permalloy patterned
on-chip. We show, from simulations and experiments, that this technology permits to exert a
finely controlled force on magnetic beads along the chip surface. This force can be tuned from few to
hundreds pN by applying a variable external magnetic field
Storing magnetic information in IrMn/MgO/Ta tunnel junctions via field-cooling
In this paper, we demonstrate that in Ta/MgO/IrMn tunneling junctions, containing no ferromagnetic elements, distinct metastable resistance states can be set by field cooling the devices from above the NĂ©el temperature (TN) along different orientations. Variations of the resistance up to 10% are found upon field cooling in applied fields, in-plane or out-of-plane. Well below TN, these metastable states are insensitive to magnetic fields up to 2 T, thus constituting robust memory states. Our work provides the demonstration of an electrically readable magnetic memory device, which contains no ferromagnetic elements and stores the information in an antiferromagnetic active layer
Magnetic domain wall tweezers: a new tool for mechanobiology studies on individual target cells
In vitro tests are of fundamental importance for investigating cell mechanisms in response to mechanical
stimuli or the impact of the genotype on cell mechanical properties. In particular, the application of controlled
forces to activate specific bio-pathways and investigate their effects, mimicking the role of the cellular
environment, is becoming a prominent approach in the emerging field of mechanobiology. Here, we
present an on-chip device based on magnetic domain wall manipulators, which allows the application of
finely controlled and localized forces on target living cells. In particular, we demonstrate the application of
a magnetic force in the order of hundreds of pN on the membrane of HeLa cells cultured on-chip, via manipulation
of 1 ÎĽm superparamagnetic beads. Such a mechanical stimulus produces a sizable local indentation
of the cellular membrane of about 2 μm. Upon evaluation of the beads’ position within the magnetic
field originated by the domain wall, the force applied during the experiments is accurately quantified via
micromagnetic simulations. The obtained value is in good agreement with that calculated by the application
of an elastic model to the cellular membrane
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