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Publications associées (520)

Electron relaxation by LO phonons in quantum wires: An adiabatic approach

Benoît Marie Joseph Deveaud, Marc-André Dupertuis

The electron states of weakly-one-dimensional quantum wires are computed using the adiabatic approximation in the framework of the k . p theory and the envelope-function approximation. The computed transition rates of electrons from one confined state to a ...

1997

Electron relaxation by LO phonons in quantum wires

Benoît Marie Joseph Deveaud, Marc-André Dupertuis

The adiabatic approximation is used to describe the electron states of weakly-one-dimensional quantum wires. A clear order is evidenced in the longitudinal optical (LO) phonon mediated transition rates with respect to the quantum numbers of the confined st ...

1997

Modeling and simulation of electromechanical transducers in microsystems using an analog hardware description language.

Philippe Renaud, Alexis Boegli

The analytical modeling and simulation of conservative electrostatic, electromagnetic and electrodynamic transducers found in microsystems using a non-linear lumped-parameter approach is presented in this paper. A comparison is made between this approach a ...

1997

Hard and soft landing of mass selected Ag clusters on Pt(111)

Klaus Kern, Harald Brune, Wolfgang Harbich, René Monot

Mass selected Ag/sub n/ clusters (n=1,7,19) from a secondary ion source have been deposited onto a Pt(111) substrate at low temperature. The surface and resulting cluster morphology have subsequently been characterized within the same UHV chamber by variab ...

1997

The effect of deliberately induced disorder on the electronic structure of the Bi-2212 high T-c superconductor

Giorgio Margaritondo, Marco Grioni

We have irradiated by thermal neutrons single crystals of the Bi-2212 high T-c superconductor. The irradiated samples are insulators, but they regain high T-c superconductivity after an annealing in He at 450-550 degrees C. Depending on irradiation doses a ...

1997

The torsional potential of perfluoro n-alkanes: a density functional study

Ursula Röthlisberger

The structural, vibrational, and conformational properties of small perfluoro n-alkanes CnF2n (n ? 5) have been studied with different d. functional models. The relative conformational energies are severely underestimated within the local d. approxn. (LDA) ...

1996

Field-Induced Manipulation Of Fullerene Molecules With The Stm - A Self-Consistent Theoretical-Study

Olivier Martin

By applying an appropriate voltage between an STM tip and a metallic substrate, it is possible to induce highly localized electrostatic fields. In this paper, it is shown that the apex of the STM probe, responsible for the resolution, confines an electric ...

Elsevier1995

Phase-Transition Mechanisms Between Hexagonal Commensurate and Incommensurate Structures

Gervais Chapuis

A hexagonal two-dimensional model of particles with displacive degrees of freedom and interacting via potential energy with harmonic and anharmonic third- and fourth-order terms has been studied by the molecular-dynamics technique. The modulated phases cha ...

1994

High resolution optical low coherence reflectometry in biological tissues

Optical low coherence reflectometry (OLCR) is a technique that permits to measure the absolute position and to determine optical properties. It is based on an interferometric method that uses a probe light characterized by a broad spectrum. Small volumes l ...

EPFL1994

Contribution à l'étude de l'érosion de cavitation

Mohamed Farhat

In the field of hydraulic power plant, the leading edge cavitation is often responsible of sever erosion which may cause a premature shutdown of energy production with costly consequences. This type of cavitation is characterized by an attached vapour cavi ...

EPFL1994

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