Evidence for long-lived quasiparticles trapped in superconducting point contacts

We have observed that the supercurrent across phase-biased, highly transmitting atomic size contacts is strongly reduced within a broad phase interval around {\pi}. We attribute this effect to quasiparticle trapping in one of the discrete sub-gap Andreev bound states formed at the contact. Trapping occurs essentially when the Andreev energy is smaller than half the superconducting gap {\Delta}, a situation in which the lifetime of trapped quasiparticles is found to exceed 100 \mus. The origin of this sharp energy threshold is presently not understood.Comment: Article (5 pages) AND Supplemental material (14 pages). To be published in Physical Review Letter

Thermal actuated micropump for biological and medical application

International audienc

Ultra-thin membrane based MEMS and NEMS technologies: actuation, sensing and energy considerations

International audienc

Prevision des seismes par la methode VAN Mission d'analyse a Thebes (Grece). Rapport final

SIGLEAvailable at INIST (FR), Document Supply Service, under shelf-number : AR 14218 / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Nanoprobes with near-infrared persistent luminescence for in vivo imaging

Fluorescence is increasingly used for in vivo imaging and has provided remarkable results. Yet this technique presents several limitations, especially due to tissue autofluorescence under external illumination and weak tissue penetration of low wavelength excitation light. We have developed an alternative optical imaging technique by using persistent luminescent nanoparticles suitable for small animal imaging. These nanoparticles can be excited before injection, and their in vivo distribution can be followed in real-time for more than 1 h without the need for any external illumination source. Chemical modification of the nanoparticles' surface led to lung or liver targeting or to long-lasting blood circulation. Tumor mass could also be identified on a mouse model