Photoluminescence enhancement in Yb^3+:Er^3+co-doped eutectic Al_2O_3: SiO_2 thin films by 980nm excitation

Abstract

Si nanocrystals (nc-Si) are addressed in the eutectic Al(2)O(3):SiO(2) thin films co-doped with Er(3+) and Yb(3+) by the laser-induced crystallization (LIC). The thin films are originally synthesized on a silica-on-silicon (SOS) substrate by the microwave electron cyclotron resonance (MW-ECR) plasma source enhanced RF sputtering. Raman spectroscopy has revealed that the strong crystallization occurs with the emergence of the nc-Si in the eutectic Al(2)O(3): SiO(2) layer during the liquid phase transformation. The dual wavelength energy transfer mechanism at 800nm and 980nm induced by 980nm excitation in nc-Si and Yb sensitized Er doped system has been proposed and demonstrated. A tenfold photoluminescence enhancement has been obtained from this mechanism.