Experimental studies of the conductance of open quantum dots show a series of highly regular oscillations at low temperatures as the voltage applied to their defining gates is varied. Simulations of quantum transport ...
Experimental studies of the conductance of open quantum dots show a series of highly regular oscillations at low temperatures as the voltage applied to their defining gates is varied. Simulations of quantum transport through these dots reveal the oscillations to be correlated to the recurrence of specific groups of wave function scars. We furthermore find that nominally identical dots, differing only in the orientation of their input and output contacts, may be used to excite different families of scars, giving rise in turn to measurable transport results.
The United States Coast Guard has embarked on the most ambitious modernization and recapitalization project in the service's history. The Deepwater Capabilities Replacement Project, which is simply referred to as ...
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The United States Coast Guard has embarked on the most ambitious modernization and recapitalization project in the service's history. The Deepwater Capabilities Replacement Project, which is simply referred to as Deepwater, is unique in that it comprises the acquisition of an entire integrated "System-of-Systems'': surface, air, (CISR)-I-4 (command, control, communications, computers, information, surveillance & reconnaissance), and logistics facilities. This "System of Systems" approach will enable the Coast Guard to acquire the optimal mix of fully supportable assets, to effectively and efficiently perform all of its Deepwater missions well into the next century.
We describe the observation of novel localization in mesoscopic quantum dots and quantum dot arrays, which are realized in high mobility GaAs/AlGaAs heterojunctions using the split-gate technique. With a sufficient ga...
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We describe the observation of novel localization in mesoscopic quantum dots and quantum dot arrays, which are realized in high mobility GaAs/AlGaAs heterojunctions using the split-gate technique. With a sufficient gate voltage applied to form the devices, their resistance diverges as the temperature is lowered below a degree Kelvin, behavior which we attribute to localization. Evidence for the localization is found over the entire range of gate voltage for which the dots are defined, persisting to conductances higher than 50 e 2 / h .
We discuss applicability of several s-z transformations to digital simulation of seismic signal propagation. Starting from a digital simulator obtained by the conventional s-z transformation, we locally optimize it wi...
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We discuss applicability of several s-z transformations to digital simulation of seismic signal propagation. Starting from a digital simulator obtained by the conventional s-z transformation, we locally optimize it with respect to an error function defined on both time and frequency domain.
This paper discusses bifurcation diagram reconstruction [1, 2] and shows by a numerical experiment that the correct bifurcation diagram of a dynamical system can be reconstructed from the signal of a chaotic dynamical...
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作者：
Benbouzid, MEHSpornic, SABody, C[?]Dr. Mohamed El Hachemi Benbouzid (1968)
SEE received the B.Sc. degree in Electrical Engineering in 1990 from the Electrical Engineering Institute of Batna University Algeria the MSc. degree in Electrical and Computer Engineering in 1991 from the National Polytechnic Instituteof Grenoble France and the Ph.D. degree also in Electrical and Computer Engineering in 1994 from the National Polytechnic Institute of Grenoble. After graduation he joined the University of Picardie-Jules Verne France where he is Associate Professor at the Professional Institute of Amiens. His currentresearch interests include electric machines anddrives computational of electromagnetics and electromechanical actuation as well as technics for energy savings. He is actually leading a research program on the monitoring and the diagnostics of induction machine drives for the French Picardie Region. He is active in the IEEE Power Engineering Society and is the treasurer of the French Chapter of the IEEE Power Electronics Society. (Laboratoire des Systkmes Automatique Universitk de Picardie-Jules Verne 7. Rue du Moulin Neuf. F-80000 Amiens France Phone: + 33 22 827680 Fax: + 33 22 82 76 82
This paper describes a model for the non-linear magnetomechanical coupling in new highly magnetostrictive materials. This model is devoted to the Computer-Aided Design of magnetostrictive devices. It is based on an it...
This paper describes a model for the non-linear magnetomechanical coupling in new highly magnetostrictive materials. This model is devoted to the Computer-Aided Design of magnetostrictive devices. It is based on an iterative process of successive magnetic and mechanical computations by a the Finite Element Method. Magnetic and mechanical quantities are still coupled by the iterative process. As a matter of fact, the use of experimental data though the Surface Spline Method allows the introduction of the magnetomechanical coupling. The experimental data are collected from a specially designed sample holder devoted to the static characterization of Terfenol-D rods. Comparisons between numerical outputs from the model and the experimental data reveal that the model is quite powerful to describe the magnetomechanical coupling in highly magnetostrictive materials as Terfonal-D. Otherwise, the proposed model has been extended to take into account the magnetostrictive effect in microsystems using highly magnetostrictive thin films. Numerical computations provide in this case coherent results and show that it is able to describe the global behaviour of highly magnetostrictive microsystems.
The modern day surface ship is composed of a number of individual systems which together operate the platform. Vital to making such a collection of systems work in this real-time environment is a common understanding ...
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The modern day surface ship is composed of a number of individual systems which together operate the platform. Vital to making such a collection of systems work in this real-time environment is a common understanding of time. As additional functions and processors are added to systems, more demands are being placed on the time distribution function. Experience has shown that currently employed techniques for time distribution are not scalable to the more distributed approaches for building shipboard control systems. Use of Commercial-Off-The-Shelf (COTS) components also drives the need for new approaches to implementing time services. This paper presents requirements for time services, an overview of current time synchronization approaches, and a technical approach being investigated for future shipboard time synchronization.
The advantages of single electron devices with asymmetrical tunnel barriers (ATBs), proposed by the authors, over conventional single electron devices with symmetrical tunnel barriers (STBs) are discussed by referring...
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The advantages of single electron devices with asymmetrical tunnel barriers (ATBs), proposed by the authors, over conventional single electron devices with symmetrical tunnel barriers (STBs) are discussed by referring to the features of ATBs and the results of computer simulation of the performance of tunnel-junction-load SET logic and turnstile devices. Experimental observation of a Coulomb staircase and asymmetrical tunnel characteristics in ATBs fabricated with GaAs/AlGaAs heterostructures are also reported.
The progress in understanding wafer-fused vertical-cavity lasers and improvements in fabrication techniques have led to the realization of the first room-temperature continuous-wave operating 1.54-/spl mu/m vertical-c...
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The progress in understanding wafer-fused vertical-cavity lasers and improvements in fabrication techniques have led to the realization of the first room-temperature continuous-wave operating 1.54-/spl mu/m vertical-cavity lasers. By demonstrating continuous-wave operation at room temperature using vertical-cavity lasers fabricated by two wafer fusion steps, we have shown that wafer fusion is a viable technique. The lasers comprise strain compensated InGaAsP quantum-well active layers sandwiched between two AlGaAs/GaAs quarter-wave mirrors. Characteristics discussed include cavity losses, the gain-current density relationship, and voltage-current characteristics.
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