Abstract

The creation of a permanent second-order susceptibility [χ⁽²⁾] for second-harmonic generation (SHG) in Ge-doped silica fibers has been reported by several authors using various techniques (exposure to IR,¹. seeding with IR and its second harmonic,² dc-field poling with blue light,³ and de field only⁴). Although the microscopic mechanism governing this interesting phenomenon is still not fully understood, it has been suggested that the alignment of defect centers plays an essential role.⁵ Defect centers, however, are known to exist or can be induced in many amorphous materials, including a variety of compound glasses that are commercially available. These commercially available compound glasses provide a wide range of options for the fiber core and cladding materials. Moreover, the effect observed to date in Ge-doped silica fibers may be present in a different and stronger form in fibers fabricated from compound glasses. It is therefore interesting to study fibers fabricated from various compound glasses. In this paper we report the first results, to our knowledge, for the dc-field poling effect in lead-silicate glass fibers.

© 1990 Optical Society of America