Posez n’importe quelle question sur les cours, conférences, exercices, recherches, actualités, etc. de l’EPFL ou essayez les exemples de questions ci-dessous.
AVERTISSEMENT : Le chatbot Graph n'est pas programmé pour fournir des réponses explicites ou catégoriques à vos questions. Il transforme plutôt vos questions en demandes API qui sont distribuées aux différents services informatiques officiellement administrés par l'EPFL. Son but est uniquement de collecter et de recommander des références pertinentes à des contenus que vous pouvez explorer pour vous aider à répondre à vos questions.
A theoretical investigation of the exciton formation process from free carriers in a single GaAs/Al1-xGaxAs quantum well is presented. The mechanism for the formation processes is provided by the interaction of the electrons and holes with phonons. The con ...
The most significant advance in this field in the past year has been the demonstration that single-crystal langasite, La3Ga5SiO14, can be used, at least at high frequencies, at temperatures up to 1000 degrees C. New evidence suggests that domain-wall contr ...
We report transient sub-picosecond pump and probe experiments performed on a semiconductor microcavity into which quantum wells have been inserted. The cavity is featuring resonance and strong coupling with the exciton. It is strongly and resonantly excite ...
A novel surveillance system for installed fiber optic cables is presented. It is based on the analysis of the local stimulated Brillouin scattering interaction. The configuration of the instrument rely on the use of a single laser source and the required l ...
Among all non-linear optical effects observed in single-mode optical fibres, stimulated Brillouin scattering (SBS) is of particular importance since it has numerous practical implications. SBS occurs when laser waves are scattered through the interaction o ...
Among all scattering processes, spontaneous Brillouin scattering originates from the interaction between light and thermal acoustic waves propagating in the medium. The interference resulting from the incident light and its spontaneously backscattered frac ...
The results of bench tests performed on a new method of combined interferometry/polarimetry for the magnetic-field reconstruction of tokamak plasmas is presented. In particular, the sensitivity obtained in the polarimetric measurement shows the feasibility ...
The authors present a new experimental method for measurement of collision-free infrared radiative lifetimes for single quantum states of a vibrationally excited sample. This method provides a more direct route to the infrared Einstein A coefficients than ...
Relative state-to-state cross sections for inelastic collisions between NO X (2) Pi(1/2) (upsilon = 20, J = 0.5, e or f) and He have been determined in a crossed molecular beam setup at a collision energy of 195 cm(-1). Efficient initial state preparation ...
Good thermal and mechanical reliability of fiber Bragg gratings are indispensable requirements for telecommunication and sensor applications. The basic model of thermal reliability is reviewed and the lifetime of Bragg gratings in different germanosilicate ...