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.
Microcavity exciton-polaritons are half-matter half-light quasiparticles with outstanding properties. This offers a great way to access and control fundamental excitations in a solid by simple optical means. Therefore, apart from their importance in fundam ...
Since the discovery of superfluidity in He-4 and Landau's phenomenological theory, the relationship between Bose condensation and superfluidity has been intensely debated. He-4 is known by now to be both superfluid and condensed at low temperature, and mor ...
We study vison excitations in a quantum dimer model interpolating between the Rokhsar-Kivelson models on the square and triangular lattices. In the square-lattice case, the model is known to be critical and characterized by U(1) topological quantum numbers ...
We investigate the superfluid-insulator quantum phase transition in a disordered one-dimensional Bose gas in the mean-field limit by studying the probability distribution of the density. The superfluid phase is characterized by a vanishing probability to h ...
Resonant Raman spectroscopy is realized on closely spaced nanowire-based quantum wells. Phonon quantization consistent with 2.4-nm-thick quantum wells is observed, in agreement with cross-section transmission electron microscopy measurements and photolumin ...
We study theoretically Bloch oscillations of half-matter, half-light quasiparticles: exciton-polaritons. We propose an original structure for the observation of this phenomenon despite the constraints imposed by the relatively short lifetime of the particl ...
The spin-1/2 Heisenberg antiferromagnets in one and two dimensions are important models in quantum magnetism in which many-body effects play a crucial role. Their collective excitations are associated with quasiparticles the interaction of which are diffic ...
After the observation of Bose-Einstein condensation in the solid state in 2006 and the demonstration on its superfluid character in 2009 the interest for the demonstration of the underlying elementary excitations – the Bogoliubov excitations – was growing. ...
In this experimental work, we optically excite the eigenmodes of an elliptical resonator in a semiconductor micro-cavity. Using a pulsed excitation, we create a superposition of eigenmodes, and image the time evolution of the coherent emission pattern. Osc ...
Spie-Int Soc Optical Engineering, Po Box 10, Bellingham, Wa 98227-0010 Usa2011
High-temperature superconductivity in copper oxides arises when a parent insulator compound is doped beyond some critical concentration; what exactly happens at this superconductor–insulator transition is a key open question1. The cleanest approach is to t ...