It has been found that the chemical state of implanted ions in SiO2 depends
on local concentration and on the transport process of the implanted eleme
nt. In this work we report the optical properties of high-energy Cu-implant
ed silica glass. 2MeV Cu+ ions were implanted at room temperature (RT) in s
ilica glass at fluences of 0.7, 3.0 and 5.0 x 10(16) ions/cm(2). The absorp
tion spectra of the as-implanted samples indicated the formation of B-2 cen
ters, but no Cu nanoparticles were formed. The photoluminescence CPL) spect
ra for excitation at 280 nm exhibited broad bands at 410 and 550 nm, associ
ated with the presence of Cu+ ions in the as-implanted samples. We discuss
the effect of thermal annealing in air on the absorption and the emission s
pectra of these Cu-implanted samples, as well as the formation of copper na
noclusters from original Cu+ ions. (C) 2001 Published by Elsevier Science B
.V. All rights reserved.