SERS-Active Pattern in Silver-Ion-Exchanged Glass Drawn by Infrared Nanosecond Laser.

The irradiation of silver-to-sodium ion-exchanged glass with 1.06-μm nanosecond laser pulses of mJ-range energy results in the formation of silver nanoparticles under the glass surface. Following chemical removal of ~25-nm glass layer reveals a pattern of nanoparticles capable of surface enhancement of Raman scattering (SERS). The pattern formed when laser pulses are more than half-overlapped provides up to ~105 enhancement and uniform SERS signal distribution, while the decrease of the pulse overlap results in an order of magnitude higher but less uniform enhancement.