High Gain, Broadband Integrated Waveguide Amplifiers

In this paper, the theory of integrated waveguide amplifier is introduced at first, its gain characteristics have been investigated by solving numerically propagation equations and rate equations at pump wavelength 980nm, some optimum projects have been introduced. Then erbium-ytterbium co-doped waveguide amplifier (EYCDWA) has been discussed .By analyzing the improved gain characteristics of EYCDWA, some instructive conclusions have been obtained.The integrated waveguide amplifier must have broadband to meet the progress of communication system. A few of feasible projects have been bring forward such as new material ,long period grating(LPG) etc. Comparing to fiber amplifier, several examples of broadband waveguide amplifier have also been particularized. The coupling between fiber and waveguide is important to the gain characteristics of EDWA. In this paper, the principle and fabrication of Si-groove have been introduced. By the method of positive-coupling and solidified with ultraviolet glue, we have realized the coupling with low loss.Planar and channel waveguides are fabricated in erbium/ytterbium co-doped phosphate glass substrate. The mode refractive index of 632.8nm wavelength, which propagates in ion-exchanged planar waveguides, is obtained by m line technology; the near figure for channel waveguide with 632.8nm waveguide is obtained. The refractive index profile of planar waveguide is obtained with inverse WKB method by measured mode refractive index.Finally, the gain characteristics of Er3+/Yb3+ co-doped phosphate glass waveguide amplifiers fabricated by ion-exchange (exchange time: 2 hours,exchange temperature:370oC) have been measured.