  In this habilitation thesis, I briefly present my work at Imperial College
London on trapping atomic clouds in micro-pyramids fabricated on silicon chips,
which led to the fabrication of an on-chip integrated atom source. Next, I
describe the research carried out at the Laboratoire de Physique des Lasers in
the SAI group. Our experiments demonstrated the temperature dependence of
near-field Casimir-Polder interactions due to thermal excitation of surface
waves, thus advancing our understanding of the dielectric properties of matter
and the quantum vacuum that surrounds it. I also present spectroscopic
experiments with atomic vapors confined in nanostructures (nano-sphere opals)
aiming at the fabrication of miniature frequency references. Finally, I explore
the possibility of performing spectroscopic experiments on molecular gases
close to surfaces.
