A THEORETICAL-STUDY OF A TI-DIFFUSED ER-LINBO3 WAVE-GUIDE LASER

A detailed theoretical procedure of determining the mode sizes of fund amental mode field distribution in a coaxially pumped Ti-diffused Er:L iNbO3 waveguide laser has been described. The mode sizes, effective re fractive indexes, effective pump area, and coupling efficiency as a fu nction of the initial Ti stripe width W were numerically calculated fo r the waveguide with 95- and 100-nm initial Ti stripe thicknesses, res pectively, The results indicated that the threshold pump power is seve rely affected by the stripe width, while slope efficiency is hardly ch anged as W; both show little difference between 95-and 100-mn stripe t hickness. In addition, the stimulated emission cross section of Er3+ i n Er:LiNbO3 channel waveguide versus the wavelength were calculated di rectly from its fluorescence spectra using the beta-tau method. Subseq uently, threshold pump power and slope efficiency were evaluated.