The Investigation Of Er/Yb Co-doped Optical Conmmunication Germinate Glasses Waveguide Material

Low phonon energy glasses doped with trivalent rare-earth ions are attractive due to their potential applications in developing compact solid-state lasers,optical broadband amplifiers and visible display devices.Currently,with operating windows in 1530-1560nm C-band erbium-doped silica fiber has become a mature product,limiting the full utilization of the channels in optical fiber.In order to further broaden the communication windows,attentions have been paid to Pr3+,Tm3+ and Ho3+ doped active optical amplifier.However,the main issue of applying the these three rare earth Pr3+,Tm3+ and Ho3+ is their low luminous efficiency,which can not achieve purposes of all-optical amplification in the second communication window,S-band and U-band.Therefore,the search for new glass matrix material for optical amplifiers with broadband and flattening gain,operating wavelength regions other than extensions to the C-band has become a top priority.Based on this consideration,Er3/Yb3+-doped low phonon energy germanium glasses were designed and synthesized,and the optical and spectral properties of Er3r were studied.K+-Na+ ion-exchange surface of the refractive index in germanium glasses were studied.In addition,the ion-exchange channek waveguide was fabricated in Er3+/Yb3+-doped germanium glasses surface prepared,and its signal gain ability wass characterizaed,laying the foundation for Pr3+,Tm3+ and Ho3+-doped germanium glasses for special-band signal amplifier.The followings are results this work achieved:1.Er3+/Yb3+ co-doped low phonon germanium glasses have been designed and fabricated.Based on optical absorption,Judd-Ofelt parameters ?2,?4 and ?6 have been derived to be.02×10-20,1.92×10-20 and 0.76×10-20cm2,respectively.Then the radiative transition probabilities,radiative lifetimes and fluorescence branching ratios were calculated.The efficient infrared emission in Er3+/Yb3+ co-doped germanium glasses system has been recorded under the pumping of a 982nm diode laser and Yi3+ is considered to be a preferable sensitizer for catching remarkable pumping energy and transferring considerable energy to Er3+.The maximum absorption and calculated emission cross sections are 5.47×10-21 cm2 and 5.76×10-21 cm2 at 1.53?m,respectively.Low maximum phonon energy and high emission cross sections indicate that Er3+/Yb3+ co-doped low phonnon germanium glasses will be promising infrared laser materials.2.The slab waveguide of alumium germanate glasses was fabricated by K+-Na+ion-exchange.Inverse Wentzel-Kramer-Brillouin(IWKB)method was applied to calculate the effective indices measured with the prism coupler technique,refractive-index profiles were fitted using Gaussian function.The maximum index change ?n and the effective diffusion constant De were calculated to be 0.01132 and 1.16×10-4?m2/s,respectively.The effect of the diffusion time on the waveguide properties was further investigated.3.K+-Na+ ion-exchanged channel waveguide amplifiers have been fabricated in Er3+/Yb3+ codoped acid-resistant alumium germanate(NMAG)glasses.The optical gain and the relative gain(the signal enhancement)of a 2.5 cm long waveguide amplifier were measured to be 9.10 dB and 8.16 dB,respectively,and after compensating both the propagation loss and the absorption loss,a maximum internal gain of?2.0 dB at 1.534 ?m was obtained,which reveals the successful employment of the thermal ion-exchange technology on the low phonon energy glasses.Based on this work,ion-exchanged Pr3+,Tm3+ and Ho3+ doped NMAG glass waveguides will bring surprises in developing O-,S-and U-band waveguide amplifiers,infrared UV-writing grating waveguide lasers and compact integrated optical devices.