DY-DOPED CHLORIDES AS GAIN MEDIA FOR 1.3 MU-M TELECOMMUNICATIONS AMPLIFIERS

We propose that Dy3+-doped chloride crystals be considered as candidat es for amplification of the 1.3 mu m signal used by the telecommunicat ions network. While several of these types of crystals can provide gai n at the specified operating wavelength of 1.31 mu m, and furthermore offer adequate bandwidth, we have focused our attention on LaCl3:Dy as an illustrative case to explore in greater depth. Spectroscopic measu rements were made on un-oriented samples of this material; excited-sta te lifetimes and LaCl3:Dy3+ Judd-Ofelt parameters are reported. Wavele ngth-resolved absorption and emission cross sections are presented for the 1.3 mu m W <----> Z band. Pump-probe measurements (using 0.92 mu m and 1.32 mu m, respectively) prove that the observed gain properties of LaCl3:Dy are consistent with those predicted on the basis of the s pectroscopic cross sections, The Dy:chloride gain media appear to have fundamental optical characteristics amenable to superior 1.3 mu m tel ecom amplifier performance, although many fabrication issues would hav e to be addressed to produce a practical amplifier.