1,036 research outputs found
Comment on "Conductance fluctuations in mesoscopic normal-metal/superconductor samples"
Recently, Hecker et al. [Phys. Rev. Lett. 79, 1547 (1997)] experimentally
studied magnetoconductance fluctuations in a mesoscopic Au wire connected to a
superconducting Nb contact. They claimed to have observed an enhancement of the
rms magnitude of these conductance fluctuations in the superconducting state
(rms(Gns)) relative to that in the normal state (rms(Gn)) by a factor of 2.8.
In this comment, we argue that the measured rms(Gns) is NOT significantly
enhanced compared to rms(Gn) when we correct for the presence of an incoherent
series resistance from the contacts, which is different when Nb is in the
superconducting or normal state.Comment: 1 pag
The Audit Logic: Policy Compliance in Distributed Systems
We present a distributed framework where agents can share data along with usage policies. We use an expressive policy language including conditions, obligations and delegation. Our framework also supports the possibility to refine policies. Policies are not enforced a-priori. Instead policy compliance is checked using an a-posteriri auditing approach. Policy compliance is shown by a (logical) proof that the authority can systematically check for validity. Tools for automatically checking and generating proofs are also part of the framework.\u
Reply to the Comment of den Hartog and van Wees on "Conductance Fluctuations in Mesoscopic Normal-Metal/Superconductor Samples"
In their comment cond-mat/9710285 [Phys. Rev. Lett. 80, 5024 (1998)] den
Hartog and van Wees (HW) raise objections against our analysis of the
experimental data presented in cond-mat/9708162 [Phys. Rev. Lett. 79, 1547
(1997)]. According to HW, we did not account for the quantum phase incoherence
introduced by the Niobium compounds of the investigated Nb/Au hybrid samples.
Here we show that and why this criticism is not justified. Some difficulties
associated with a precise determination of the coherence lengths are discussed.
It is discussed why these uncertainties do not have a qualitative impact on the
results reported in our paper.Comment: Reply to the comment cond-mat/9710285 by den Hartog and van Wees; 1
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Reentrant behavior in the superconducting phase-dependent resistance of a disordered 2-dimensional electron gas
We have investigated the bias-voltage dependence of the phase-dependent
differential resistance of a disordered T-shaped 2-dimensional electron gas
coupled to two superconducting terminals. The resistance oscillations first
increase upon lowering the energy. For bias voltages below the Thouless energy,
the resistance oscillations are suppressed and disappear almost completely at
zero bias voltage. We find a qualitative agreement with the calculated
reentrant behavior of the resistance and discuss quantitative deviations.Comment: 4 pages, 5 figures, to be published in Phys. Rev.
Antecedents and outcomes of Hungarian nurses’ career adaptability
Purpose: With the ageing global population the demand for nursing jobs and the requirements for complex care provision are increasing. In consequence, nursing professionals need to be ready to adapt, obtain variety of skills, and engage in career self-management. The current study investigates individual, micro-level, resources and behaviors that can facilitate matching processes between nursing professionals and their jobs. Design/methodology/approach: A survey-based study was conducted among 314 part-time and full-time nursing professionals in Hungary. Findings: Consistent with the career construction theory, this study offers evidence on career adaptability as a self-regulatory resource that might stimulate nurses’ adaptation outcomes. Specifically, it demonstrates positive relationships between adaptive readiness (proactive personality and conscientiousness), career adaptability, adapting behaviors (career planning and proactive skill development) and adaptation outcomes (employability and in-role performance). Research limitations/implications: The cross-sectional design limits causal inference. Relatively small sample of full-time professionals for whom supervisory-ratings were obtained yields the need of further replication. Practical implications: Stimulating development of nurses’ career adaptability, career planning, and proactive skill development can contribute to sustainable career management. It can facilitate the alignment of nurses to performance requirements of their current jobs, preventing individual person-job mismatch. Originality/value: Zooming into the context of nursing professionals in Hungary, the study elucidates the understudied link between adaptivity and adapting responses and answers the call for more research that employs other-ratings of adaptation outcomes. It demonstrates the value of career adaptability resources for nurses’ employability and in-role performance
High resolution charge-exchange spectroscopic measurements of aluminum impurity ions in a high temperature plasma
Charge-exchange recombination spectroscopy, which is generally used to measure low-Z impurities in fusion devices, has been used for measuring Al+11 and Al+13 impurities in the Madison Symmetric Torus reversed field pinch. To obtain the impurity ion temperature, the experimental emission spectrum is fitted with a model which includes fine structure in the atomic transition. Densities of these two ionization states, calculated from charge-exchange emission brightness, are used in combination with a collisional radiative model to estimate the abundance of all other charge states of aluminum in the plasma and the contribution of aluminum to the effective ionic charge of the plasma
reentrance effect in normal-metal/superconducting hybrid loops
We have measured the transport properties of two mesoscopic hybrid loops
composed of a normal-metal arm and a superconducting arm. The samples differed
in the transmittance of the normal/superconducting interfaces. While the low
transmittance sample showed monotonic behavior in the low temperature
resistance, magnetoresistance and differential resistance, the high
transmittance sample showed reentrant behavior in all three measurements. This
reentrant behavior is due to coherent Andreev reflection at the
normal/superconducting interfaces. We compare the reentrance effect for the
three different measurements and discuss the results based on the theory of
quasiclassical Green's functions
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