5,316 research outputs found
Muon localization site in U(Pt,Pd)3
The angular and temperature (10-250 K) variation of the Knight shift of
single-crystalline U(Pt0.95Pd0.05)3 has been measured in transverse field
(B=0.6 T) mSR experiments. By analysing the temperature variation of the Knight
shift with a modified Curie-Weiss expression the muon localization site in this
hexagonal material is determined at (0,0,0).Comment: 12 pages (including 4 figures); postscript file; Proc. 8th Int. Conf.
on Muon Spin Rotation, Relaxation and Resonance (Aug.30-Sept.3, Les
Diablerets); 2nd version with minor correction
Decoherence induced by squeezing control errors in optical and ion trap holonomic quantum computations
We study decoherence induced by stochastic squeezing control errors
considering the particular implementation of Hadamard gate on optical and ion
trap holonomic quantum computers. We find the fidelity for Hadamard gate and
compute the purity of the final state when the control noise is modeled by
Ornstein-Uhlenbeck stochastic process. We demonstrate that in contradiction to
the case of the systematic control errors the stochastic ones lead to
decoherence of the final state. In the small errors limit we derive a simple
formulae connecting the gate fidelity and the purity of the final state.Comment: RevTex, 5 pages, few typos correcte
Driver-pressure-impact and response-recovery chains in European rivers: observed and predicted effects on BQEs
The report presented in the following is part of the outcome of WISER’s river Workpackage WP5.1 and as such part of the module on aquatic ecosystem management and restoration. The ultimate goal of WP5.1 is to provide guidance on best practice restoration and management to the practitioners in River Basin Management. Therefore, a series of analyses was undertaken, each of which used a part of the WP5.1 database in order to track two major pathways of biological response: 1) the response of riverine biota to environmental pressures (degradation) and 2) the response of biota to the reduction of these impacts (restoration). This report attempts to provide empirical evidence on the environment-biota relationships for both pathways
Magnetism in heavy-fermion U(Pt,Pd)3 studied by mSR
We report mSR experiments carried out on a series of heavy-electron
pseudobinary compounds U(Pt1-xPdx)3 (x<=0.05). For x<=0.005 the zero-field muon
depolarisation is described by the Kubo-Toyabe function. However the
temperature variation of the Kubo-Toyabe relaxation rate does not show any sign
of the small-moment antiferromagnetic phase with TN~6 K (signalled by neutron
diffraction), in contrast to previous reports. The failure to detect the small
ordered moment suggests it has a fluctuating (> 10 MHz) nature, which is
consistent with the interpretation of NMR data. For 0.01<=x<=0.05 the muon
depolarisation in the ordered state is described by two terms of equal
amplitude: an exponentially damped spontaneous oscillation and a Lorentzian
Kubo-Toyabe function. These terms are associated with antiferromagnetic order
with substantial moments. The Knight-shift measured in a magnetic field of 0.6
T on single-crystalline U(Pt0.95Pd0.05)3 in the paramagnetic state shows two
signals for B perpendicular to c, while only one signal is observed for B||c.
The observation of two signals for B perpendicular to c, while there is only
one muon localisation site (0,0,0), points to the presence of two spatially
distinct regions of different magnetic response.Comment: 25 pages including 12 figures (PS), J. Phys.: Condens. Matter, in
prin
Benchmarking high fidelity single-shot readout of semiconductor qubits
Determination of qubit initialisation and measurement fidelity is important
for the overall performance of a quantum computer. However, the method by which
it is calculated in semiconductor qubits varies between experiments. In this
paper we present a full theoretical analysis of electronic single-shot readout
and describe critical parameters to achieve high fidelity readout. In
particular, we derive a model for energy selective state readout based on a
charge detector response and examine how to optimise the fidelity by choosing
correct experimental parameters. Although we focus on single electron spin
readout, the theory presented can be applied to other electronic readout
techniques in semiconductors that use a reservoir.Comment: 19 pages, 8 figure
Composition profiling InAs quantum dots and wetting layers by atom probe tomography and cross-sectional scanning tunnelling microscopy
This study compares cross-sectional scanning tunnelling microscopy (XSTM) and
atom probe tomography (APT). We use epitaxially grown self-assembled InAs
quantum dots (QDs) in GaAs as an exemplary material with which to compare these
two nanostructural analysis techniques. We studied the composition of the
wetting layer and the QDs, and performed quantitative comparisons of the indium
concentration profiles measured by each method. We show that computational
models of the wetting layer and the QDs, based on experimental data, are
consistent with both analytical approaches. This establishes a link between the
two techniques and shows their complimentary behaviour, an advantage which we
exploit in order to highlight unique features of the examined QD material.Comment: Main article: 8 pages, 6 figures. Appendix: 3 pages, 5 figure
Colloidal carbon particles as a new label for rapid immunochemical test methods: quantitative computer image analysis of results
Colloidal carbon particles can serve as label in sol particle immunoassays. The universal applicability of these particles in qualitative and (semi)quantitative immunoassays has been demonstrated. Sol particle and/or dipstick immunoassays, not yet optimized in terms of sensitivity, are discussed.\ud
\ud
The colloidal label has been used successfully in a mouse immunoglobulin isotyping kit. Human serum albumin spotted onto nitrocellulose in a concentration range of 7.8 to 1000 ng could be detected using anti-albumin antibody adsorbed onto colloidal carbon particles. It was also possible to perform a competitive assay with this conjugate for a concentration range of free human serum albumin varying from 0.25 to 6.75 ¿g. The Kunitz-type trypsin inhibitor from soybean was determined by a colloidal carbon based immunoassay in a range of 2.5 to 160 ng. In this assay, free and colloidal carbon-bound inhibitor competed for binding specific antibodies spotted onto a nitrocellulose membrane.\ud
\ud
An image- and data-processing procedure has been developed that enables a rapid and simple quantification of colloidal carbon sol particle immunoassays. The average grey level of a spot is taken as a measure for quantitative purposes. This so-called Sol-particle Image Processed ImmunoAssay (SIPIA) procedure is equally well applicable to assays using other colloidal particles
Risks in major innovation projects, a multiple case study within a world's leading company in the fast moving consumer goods
This paper investigates which risks characterise radical innovation projects. In-dept case studies were carried out via interviews and a questionnaire. The risk concept applied in this study includes three dimensions: certainty, controllability and impact. Three structural or unambiguous risks were found: new product performance according to specification, reliability of suppliers and new product adoption by consumers. The incidental or ambiguous risks that were found relate to: internal organisation and project management. These results can provide guidance for project teams and innovation managers regarding issues they must seek to tick off early and issues that continuously require team and management attention
Trajectory Deflection of Spinning Magnetic Microparticles, the Magnus Effect at the Microscale
The deflection due to the Magnus force of magnetic particles with a diameter
of 80 micrometer dropping through fluids and rotating in a magnetic field was
measured. With Reynolds number for this experiment around 1, we found
trajectory deflections of the order of 1 degree, in agreement within
measurement error with theory. This method holds promise for the sorting and
analysis of the distribution in magnetic moment and particle diameter of
suspensions of microparticles, such as applied in catalysis, or objects loaded
with magnetic particles.Comment: 12 pages, 3 figures. Appendix with 6 figure
- …
