Abstract

Since the discovery¹ of efficient second harmonic generation (SHG) in Ge/P doped fibers after exposure to intense light at 1064 nm, many research groups have reported the creation of a permanent second-order susceptibility [χ⁽²⁾] using various techniques^2,3 based on light excitation. We have discovered that a permanent χ⁽²⁾ for SHG in silica fibers can be induced by a strong dc electric field without light.

© 1990 Optical Society of America