基于铒镱共掺纳米晶的聚合物光波导放大器的增益特性

Gain Characteristics of Polymer Waveguide Amplifiers Based on Er^(3+),Yb^(3+)Co-Doped Nanocrystals

通过理论模拟和计算对基于氟钇钠(Na YF4)∶镱(Yb^(3+)),铒(Er^(3+))纳米晶的聚合物光波导放大器在1.55 mm处的增益特性进行了研究。分析中采用的波导芯层为Na YF4∶18%Yb^(3+),10%Er^(3+)纳米晶掺杂的SU-8 2005聚合物,包层为P(MMAGMA)聚合物。通过测试和分析纳米晶材料的吸收光谱和荧光光谱,利用Judd-Ofelt理论计算出了相应的Judd-Ofelt参数:Ω2=6.302×10-20cm2,Ω4=0.69×10-20cm2,Ω6=7.572×10-20cm2。通过求解原子速率方程与光功率传输方程模拟分析了波导放大器在1.55μm波长的增益特性,得到的增益曲线具有饱和效应,当Er^(3+)离子浓度为7.5×1025m-3时获得的最大增益为9.7 d B。以Si O2作为下包层,Na YF4∶Yb^(3+),Er^(3+)纳米晶掺杂的SU-8 2005聚合物作为芯层,P(MMA-GMA)聚合物作为上包层,制备了聚合物光波导放大器,当波长为980 nm的抽运光功率为170 m W、信号光功率为0.1 m W时,器件获得的最大相对增益为3.42 d B/cm。

Gain characteristics of waveguide amplifiers based on SU-8 2005 doped with Na YF4∶18%Yb^3＋, 10%Er^3＋nanocrystals（NCs） at 1.55μmm wavelength are investigated through numerical simulations. Na YF4∶18%Yb^3＋,10%Er^3＋NCs are doped into SU-8 2005 polymer matrix as the core of the polymer waveguide, and the P（MMA-GMA）polymer is used as the top cladding. The absorption spectrum and photoluminescence spectrum of the NCs are measured and analyzed. The Judd- Ofelt parameters are achieved by means of Judd- Ofelt theory：Ω2= 6.302 × 10^-20cm^2, Ω4= 0.69 × 10^-20cm^2, Ω6= 7.572 × 10^-20cm^2. The gain characteristics of the waveguide amplifier at 1.55 μm wavelength are simulated by combining the power propagation equations as well as the atomic rate equations. The gain curves have the saturation effects. The maximum gain of 9.7 d B with the Er^3＋concentration of7.5×10^25m^-3is obtained. The top cladding of the waveguide amplifier with SU- 8 doped with Na YF4∶Yb3 ＋, Er3 ＋nanocrystals is P（MMA-GMA）, and bottom cladding is Si O2, respectively. For input signal power of 0.1 m W and980 nm pump power of 170 m W, a relative optical gain of 3.42 d B/cm at 1550 nm is obtained.