Entangled Bell states of two electrons in coupled quantum dots—phonon decoherence

We demonstrate coupling and entangling of quantum states in a pair of vertically aligned self assembled quantum dots by studying the dynamics of two interacting electrons driven by external electric field. The present entanglement involves the spatial degree of freedom for the two electrons system. We show that system of two interacting electrons initially delocalized (localized each in one dot) oscillate slowly in response to electric field, since the strong Coulomb repulsion makes them behaving so. We use an explicit formula for the entanglement of formation of two qubit in terms of the concurrence of the density operator. In ideal situations, entangled quantum states would not decohere during processing and transmission of quantum information. However, real quantum systems will inevitably be influenced by surrounding environments. We discuss the degree of entanglement of this system in which we introduce the decoherence effect caused by the acoustic phonon. In this entangled states proposal, the decohering time depends on the external parameters.     

Systeme Binaire AgNO3-LiNO3. Diagramme de phases et proprietes thermodynamiques des mélanges a l’etat liquide

To study the coherence of thermodynamic data of the AgNO₃-LiNO₃ -RbNO₃ ternary system, phase diagram of the binary system AgNO₃ -LiNO₃ has been obtained between 303 and 550 K by direct and differential thermal analysis technique. This system is characterized by an eutectic point (25% mol. LiNO₃ , 445±1 K) and a plateau due to the solid-solid transition in AgNO₃ at 434±1 K. In the solid state the solubility of each component in the other seems to be nil or negligible (no more than a few percents). Using other thermodynamic data, the excess properties of the binary liquid (AgNO₃ - LiNO₃ ) were calculated at 623 K. This revised version was published online in August 2006 with corrections to the Cover Date.     

A weight-function approach for determining watershed initial conditions for combustion waves

In many generic combustion models, one finds that a combustionwave will develop with a specific wave speed. However, thereare possible initial temperature profiles which do not evolveinto such waves, but rather die out to the ambient temperature.There can exist, in some models, a clear distinction betweenthose initial conditions that do evolve into combustion wavesand those that do not; this is sometimes referred to as thewatershed initial condition. When fuel consumption is consideredto be negligible, analytical methods can be used to obtain theexact watershed. In this paper, we consider the problem of determiningpseudo-watersheds and ascertaining the relationship betweenthese pseudo-watersheds and the exact watersheds. In the processa novel weight-function approach for infinite spatial domainsis developed.     

Effect of temperature on copper indium selenization

The reaction kinetics of copper indium diselenide formation is studied by measuring species composition as a function of time at 250°C and 325°C in a tubular chemical vapor deposition reactor. This extends our previous modeling and experimental study at 400°C. The initial copper–indium alloy is analyzed at the reaction temperatures using high-temperature X-ray diffraction measurements. This modifies the understanding of the chemistry of the copper indium growth kinetics and a new set of model equations is presented. The specific reaction rate constants and activation energies for the chemical reactions are obtained, enabling one to calculate the holding time for the reaction. © 1997 John Wiley & Sons, Ltd.     

Diagramme de phases du systeme binaire AgNO3—RbNO3

Phase diagram of the binary system AgNO₃—RbNO₃ was studied using thermal analysis technique, differential scanning calorimetry and X-ray diffraction. This binary exhibits a congruently melting compound Ag_0.5Rb_0.5NO₃ (m. p.=138°C), an incongruently melting one Ag_0.33Rb_0.66NO3 with two polymorphic varieties, two eutectics at (36 mol% RbNO₃, 128°C) and at (60 mol% RbNO₃, near 134°C) respectively and a peritectic at (60.5 mol% RbNO₃, 141°C). This system contains also three invariant reactions at 164, 222 and 282°C due to the phase transitions of RbNO₃ and another one at 164°C due to the phase transition of AgNO₃.

Ce travail a été présenté aux 32èmes JCAT, tenues à Hammamet, TN, du 12 au 14 Mai 2001.     

Candidate architectures for emerging IoV: a survey and comparative study

Intelligent Transportation System (ITS) is observing significant evolution in terms of technology and investment worldwide. This has given birth to the new concept of Internet of vehicles (IoV) as one of the leading applications of the Internet of Things. IoV aims to offer a better sharing of information and communication between vehicles, enabling higher cooperation for common interests. IoV is increasingly attracting the interest of a significant body of research. The e ort was mostly focused on solving various problems encountered in traditional VANETs, such as lack of coordination between vehicles, insufficient information, scalability, etc. Rapidly, IoV observed, particularly interesting advances taking advantage of exponential growth in communication and data analysis technologies. This includes cloud and/or fog computing, large data analytics, machine learning, and artificial intelligence. In this paper, we make a survey of the existing and recently proposed architecture solutions for IoV systems. Moreover, we define a list of criteria, features, and properties associated to the various architectures in order of making critical and insightful comparisons and assessments. Finally, we outline the key future research perspectives on the topic and define the key technical aspects that will help drive the future of IoV architectures.