scispace - formally typeset
Search or ask a question

Showing papers by "Philip St. J. Russell published in 1992"


Journal ArticleDOI
TL;DR: The study reveals that Hi-Bi fibers are insensitive to light polarized along the fast axis, in contrast to Lo- bi fibers, which are photosensitive along both axes, and the significance of the results to models based on stress and/or glass defects is briefly discussed.
Abstract: A study of photoinduced birefringence in bow-tie (stress-induced) high-birefringence (Hi-Bi) and low-birefringence (Lo-Bi) germanosilicate optical fibers is conducted by using 532-nm light. The study reveals that Hi-Bi fibers are insensitive to light polarized along the fast axis, in contrast to Lo-Bi fibers, which are photosensitive along both axes. The induced birefringence in Lo-Bi fibers is reversible, whereas the change in Hi-Bi fibers is permanent. The sign of the induced birefringence is established experimentally for the first time to our knowledge, and the significance of the results to models based on stress and/or glass defects is briefly discussed.

112 citations


Journal ArticleDOI
TL;DR: The photonic band gap (PBG) as discussed by the authors has been proposed as an analogy with the electronic band gap in semiconductor crystals and has been shown to be useful in the field of dielectric structures.
Abstract: Many major discoveries in physics this century originate from the study of waves in periodic structures. Examples include X-ray and electron diffraction by crystals, electronic band structure and holography. Analogies between disciplines have also led to fruitful new avenues of research. An exciting example is the recent discovery of three-dimensionally periodic dielectric structures that exhibit what is called a "photonic band gap" (PBG), by analogy with electronic band gaps in semiconductor crystals. Photons in the frequency range of the PBG are completely excluded so that atoms within such materials are unable to spontaneously absorb and re-emit light in this region; this has obvious beneficial implications for producing highly efficient lasers. Given that electrons and photons obey almost the same differential wave equation, the idea of a PBG is clearly far from crazy. It does, however, demand a radical rethink of how light behaves in periodic structures.

62 citations