Polymer Green Light Waveguide Amplifiers Based On Yb³⁺-Er³⁺Co-Doped Nanocrystals

Since the wavelength radiated from the energy level4I13/2â†'4I15/2of erbium iondoped in erbium-doped waveguide amplifiers (EDWA) radiation matches with theminimum loss optical communication network communication window (regularband:1530~1565nm), EDWA have attracted more and more attention. However, inrecent years, the plastic optical fiber developed rapidly. It has the advantage of thewell flexibility, easy wiring and connection, which make it play a special role in thecabling of the family in the last kilometer of FTTH system. It is also helpful topromote the realization of the tri-networks integration, and its market prospects isvery good. Because the network equipments used in the plastic optical fibertransmission systems are mainly based on650nm and540nm wavelength laser, thecorresponding visible optical devices has become the core facility of thecommunication network system.In this thesis, BaLuF5: Yb3+, Er3+nanocrystals were synthesized with themethod of high-temperature thermal decomposition, and the crystal structure,morphology, and the near infrared emission characteristic of the nanocrystals werealso characterized and testing. The average particle diameter of nanocrystals wasabout13nm. The nanocrystals presented strong emission at1530nm. Thefluorescence emission spectrum showed that the full width at half maximum is about50nm. The synthesized BaLuF5: Yb3+, Er3+nanocrystals were doped into the SU-8polymer as the core material of the optical waveguide amplifiers. The waveguideamplifier was fabricated using conventional semiconductor fabrication processes.When the pump power is280mW and the signal power is0.1mW, a relative opticalgain of3.95dB was obtained at1530nm wavelength in a1.1-cm-length waveguide.The green upconversion phenomenon was clearly observed in the erbiumytterbium co-doped nanocrystals doped polymer waveguide amplifier with980nmpumped. Due to the rapid development of the visible light communication in recent years, the gain characteristics of polymer waveguide amplifiers based on NaYF4:Yb3+, Er3+nanocrystals at0.54μm wavelength were investigated through numericalsimulations for the first time. The optimized cross section size of waveguide was1μm×1μm. The gain characteristics of the waveguide amplifier at0.54μmwavelength were simulated by combining the atomic rate equations with powerpropagation equations. When the Er3+concentration is about7.5×1025m-3and thesignal power is0.01mW, maximum gain of approximately4.3dB was obtained in a5-cm-length waveguide.