Laser-Induced Formation of Molecular Barriers in Porous Glass

Abstract

The possibility of creating physical barriers with various degrees of permeability in porous glass (PG) plates by local variation in the density of the porous structure of the matrix is demonstrated. The compaction of PG in the volume is provided by exposure to femtosecond laser pulses, while the surface impermeability of the compaction areas is provided by exposure to radiation of the CO₂ laser. This approach to control the density of the PG structure makes it possible to create molecular barriers that represent a physical and/or chemical boundary for molecules located in a porous matrix (with controlled permeability). The discussed technology of the local porosity control opens the way to designing integral photon, fluid, and other types of devices based on PG plates.