Optical characterization and manipulation of alkali metal nanoparticles in porous silica A. Burchianti, A. Bogi, C. Marinelli, C. Maibohm, E. Mariotti, S. Sanguinetti and L. Moi Eur. Phys. J. D, 49 2 (2008) 201-210 Published online: 22 August 2008 DOI: 10.1140/epjd/e2008-00164-5