Fiber and Planar Waveguide Amplifiers Based on Heavy Metal Oxide Glasses

Glass fiber and planar waveguide devices play an important role in both optical communication and optical signal processing systems. With the ever increasing implementation of optical fiber systems in trunk and access networks, there is an increasing demand on advanced optical components to fully utilize the enormous channel capacity of optical fibers. Rare earth doped glass materials are attractive for developing solid state lasers and optical amplifiers. To date, erbium (Er3+) ions have been the most popular rare earth dopant for commercial optical amplifiers, and erbium doped fiber amplifiers (EDFAs) and erbium doped waveguide amplifiers (EDWAs) based on silicate and phosphate glass materials are key devices for wavelength division multiplexing (WDM) transmission systems operating-in the conventional C-band (1530nm-1565nm) telecommunication window. Er3+doped silicate and phosphate glass fiber and waveguide devices have great successes in commercial C-band amplifiers and lasers.There is a demand for optical amplifiers that operate at wavelengths other than 1550nm wavelength , and efforts are needed to develop praseodynium (Pr3+), thullium (Tm3+), and holmium (Ho3+) doped glass fiber and planar waveguide amplifiers operating in the original (O-band,1260nm-1360nm), short wavelength (S-band,1460nm-1530nm) and ultralong (U-band,1625nm-1675nm) bands to fully exploit the potential transmission bandwidth and meeting the need of modern all-optical WDM networks. However, these rare earth ions operating at other wavelengths require advanced materials that are more difficult to make and process. It is a challenge to make, engineer, and process glass materials that have low phonon energy, high rare earth solubility, broad gain bandwidth and high efficiency.In this project, rare earth doped heavy metal oxide glass material technology will be further developed at City University of Hong Kong. Stable praseodynium (Pr3+), thullium (Tm3+), and holmium (Ho3+) doped low-phonon heavy metal oxide glasses with better chemical and thermal durability than fluoride glasses will be made. Fiber and planar waveguides devices based on these glasses will be fabricated, with applications as optical amplifiers in the O-, S- and U- bands. The realization of these optical amplifiers will have great impact and increase further the available bandwidth in high-capacity optical communication systems.