Are low-loss glass ceramic optical waveguides possible?

The results of a cutback measurement of a glass-ceramic optical waveguide with single-mode fiber geometry have demonstrated that sub decibels per kilometer losses can be achieved. Difference spectra show that the limit of intrinsic scattering in these two-phase structures ought to be tens of decibels per kilometer.

Athermal glass for the infrared.

Refractive indices of four CLAP glass systems are measured at room temperature and at higher temperatures in the wavelength range of 0.4-5.5 microm. The coefficients of temperature changes of optical path lengths are calculated and are <1 x 10(-6)/ degrees C in the wavelength range longer than 1microm. This suggests an athermal glass application in the infrared ray region.

Efficient neodymium-doped glass-ceramic fiber laser and amplifier.

We report an efficient glass-ceramic fiber laser and show that its slope efficiency (~30%) is not compromised by the presence of Nd-doped fluoride crystals embedded within the core of the single-mode optical fiber. In contrast, the spectroscopy (fluorescence and gain spectrum) of the Nd(3+) ions is dramatically changed by the ceramming process, an indication of strong partitioning of the rare-earth ions into the CdF(2):PbF(2):YF(3) crystal environment. The enormous potential for a new range of optical devices based on transparent glass-ceramic materials is highlighted.

Photorefraction in lead tin-fluorophosphate glasses.

Permanent grating patterns have been written directly in lead-tin-fluorophosphate glasses by use of UV radiation. The effect of photorefraction is studied in different tin-fluorophosphate compositions. Recorded gratings are found to be volume rather than surface elements. The induced index changes are comparable with those seen in GeO(2)- SiO(2) glasses.