The Upconversion Luminescence Investigation Of Er/Yb Codoped System And Band Gaps Computation Of Photonic Crystals

Series of silicate glasses with Er³⁺/Yb³⁺ co-doped and Er³⁺-doped were fabricated byhigh-temperature solid-state reaction. With the combining of the energy transmission modebetween Er³⁺-Yb³⁺, photolurninescence property of Er³⁺/Yb³⁺ doped samples at differentwaveband were analyzed. The infrared and visible light emissions of Er³⁺ have been observed.The introduction of Yb³⁺ causes the pumping efficiency of Er³⁺ has dramatic increase, makesthe activity of Er³⁺ increase. In series of Er³⁺ doped sample, the photoluminescence intensityfor infrared emission has slowly increased along with the concentration. of Er³⁺ ion. In seriesof Er³⁺/Yb³⁺ codoped samples, the photoluminescence intensity for infrared emission have aoptimal value with the concentration of 0.1at% Er³⁺ and 0.7at% Yb³⁺, and enhance by a factorof about 14 compared with that of 0.1at% Er³⁺ doped sample; The most value for visibleemission intensity was obtained with the the concentration of 0.5at% Er³⁺ and 0.9at% Yb³⁺,and two orders of magnitude enhancement was observed.The dependence of the up-conversion emission intensity on the temperature in Er³⁺/Yb³⁺codoped and Er³⁺ doped silicate glass excited at 980nm was measured. A model based on therate equations considering the temperature dependence multiphonon-assisted excitation andnon-radiative transition theories describes well the experiment phenomena. Fivefold intensityenhancement of the up-conversion green fluorescence emission has beeen obtained astemperature was changed from 296K to 723K. Using the green emission of Er³⁺, Thetemperature dependence of fluorescence intensity ration (FIR) was investigated. Experimentresult show, the thermometry range is excessively extended in silicate glass because of thehigh vitreous transition temperature. Utilizing the energy transfer among Er³⁺, Nd³⁺ and Yb³⁺,the emission intensity of Nd³⁺ have been improved at interested wave band. The temperatureeffect on the multi-wavelength, and the FIR between 813nm and 887nm was investigated, andsensitivity of 0.0035K^-1 has been obtained.The films of Er³⁺/Yb³⁺ codoped Al₂O₃ and silicate glass have been prepared by pulselaser deposition (PLD), respectively. Utilizing the instrument of SEM, AFM, EPMA andluminescence detecting, the experimental parameters have been optimized simply. The bendEr³⁺/Yb³⁺ codoped waveguide amplifier has been designed and etched, and transmissionproperty of bend waveguide have been simulated by Beam Propagation Method (BPM). The bend loss of 2.351×10^-4dB/cm was obtained. The mask deposition is proposed, and linewaveguide has been deposited by this method.Photonic crystal waveguide amplifier is proposed. Photonic band gaps have beenanalysed on Er³⁺ doped Al₂O₃, silicate glass and Si by plane-wave expansion technique, andphotonic crystal structures suited for photonic crystal waveguide amplifier have beenanalysed.