Search results for "Wire"

The quantum phase slip phenomenon in superconducting nanowires with a low-Ohmic environment

2012

In a number of recent experiments it has been demonstrated that in ultra-narrow superconducting channels quantum fluctuations of the order parameter, alternatively called quantum phase slips, are responsible for the finite resistance well below the critical temperature. The acceptable agreement between those experiments and the models describing quantum fluctuations in quasi-one-dimensional superconductors has been established. However the very concept of the phase slip is justified when these fluctuations are the relatively rare events, meaning that the effective resistance of the system should be much smaller than the normal state equivalent. In this paper we study the limit of the strong…

Phase Slip Phenomena in Ultra-Thin Superconducting Wires

2006

We present results on phase-slip phenomena in a superconducting wire which can be considered as quasi-one dimensional (1D) if its characteristic transverse dimension \( \sqrt \sigma\) (√ being the cross section) is smaller than the coherence length Λ(T). The shape of the bottom part of the resistive transition R(T) of a 1D superconducting strip is described by the model of phase slips activation. If the wire is infinitely long, then there is always a finite probability that a small part of the sample is instantly driven normal.

Experimental Study of the Fluctuation-Governed Resistive State in Quasi-One-Dimensional Superconductors

2011

Physical properties of quasi-one-dimensional superconducting channels (nanowires) can differ significantly from those of bulk superconductors. The reason behind is the impact of thermal and quantum fluctuations. In the particular case of resistive measurements the fluctuations may significantly broaden the superconducting transition R(T). Here we review the activities in the field with main emphasis on experiment, while brief theoretical background is also presented.

Size-dependent enhancement of superconductivity in Al and Sn nanowires: shape-resonance effect

2006

A shape-dependent superconducting resonance can be expected when an energy level associated with the transverse motion in a wire passes through the Fermi surface. We show that the recently observed width-dependent increase of ${T}_{c}$ in Al and Sn nanowires is a consequence of this shape-resonance effect.

An Innovative Shelf Life Model Based on Smart Logistic Unit for an Efficient Management of the Perishable Food Supply Chain

2015

Despite the recent interest towards food safety and control, it is generally difficult to ensure full products traceability through industrial food chains, due to the lack of efficient information and communication systems. Consequently, nowadays, the protection of food products often ends at the gates of the producer without any investigation about the status of their quality at the consumer's location. The aim of this paper was the development of a supply chain monitoring system based on a smart logistic unit (SLU) to support the integrated management of the food supply chain from “farm to fork” in order to guarantee and control food safety and shelf life (SL) of products in agreement wit…

Spectrum Hole Detection for Cognitive Radio through Energy Detection using Random Forest

2020

The growth of wireless data is the major driving force for an exponential increase in wireless communication. Cognitive Radio is one of the emerging wireless technologies that can be used for smart utility networks. Optimum utilization of the wireless spectrum is the objective of Cognitive Radio. Finding a spectrum hole through intelligent means is essential for the success of Cognitive Radio. Dynamic spectrum allocation is also an efficient technique for spectrum allocation. It will lead to a better spectrum utilization. In this paper, some of the machine learning techniques are used to find a frequency range for dynamic spectrum allocation. Different machine learning techniques such as Lo…

Optimal gossip algorithm for distributed consensus SVM training in wireless sensor networks

2009

In this paper, we consider the distributed training of a SVM using measurements collected by the nodes of aWireless Sensor Network in order to achieve global consensus with the minimum possible inter-node communications for data exchange. We derive a novel mathematical characterization for the optimal selection of partial information that neighboring sensors should exchange in order to achieve consensus in the network. We provide a selection function which ranks the training vectors in order of importance in the learning process. The amount of information exchange can vary, based on an appropriately chosen threshold value of this selection function, providing a desired trade-off between cla…

On the Interaction of Carbon Nanowires with Noble Metals through a Study of Their Surface-Enhanced Raman Spectra

2008

This paper deals with the interaction of linear carbon chains (polyynes) with silver and gold surfaces in the form of nanometer-sized clusters. Surface-enhanced Raman signals have been detected rev...

From Single Molecules to Nanoscopically Structured Functional Materials: Au Nanocrystal Growth on TiO2 Nanowires Controlled by Surface-Bound Silicate…

2006

Fabrication and characterization of ZnO nanowires/CdSe/CuSCN eta-solar cell

2006

Des cellules solaires extremely thin absorber (eta) ZnO/CdSe/CuSCN a base de nanofils de ZnO ont ete realisees avec succes en utilisant des techniques faciles d'acces de depot en solution et par voie electrochimique. Une couche constituee de nanofils de ZnO monocristallin de plusieurs microns de hauteur et de 100-200 nm de diametre a ete deposee sur un substrat de verre conducteur (SnO 2 :F) recouvert d'une couche de ZnO formee par pyrolyse de spray agissant comme couche electronique bloquante. Une couche mince de 30-40 nm de CdSe jouant le role d'un absorbeur a ete electrodeposee de maniere conforme le long des nanofils de ZnO. Les espaces entre les nanofils composite de ZnO/CdSe ont ete r…