High-temperature optical properties of sensitized Er3+ in Si-rich SiO2 - implications for gain performance

The high-temperature photoluminescence of Er-doped Si-rich SiO2 with and without silicon nanocrystals is studied at sample temperatures in the range 20-200 degrees C. The optical properties of Er-doped Si-rich SiO2 with and without silicon nanocrystals are shown to exhibit a similar temperature dependence. Based on the measured photoluminescence intensities and lifetimes it is predicted that an increase of the sample temperature from 20 to 200 degrees C results in a decrease of the maximum optical gain at 1535 nm by a factor of similar to 1.8 and similar to 1.6 for samples with and without silicon nanocrystals, respectively. Implementation of this material in silicon photonics requires stable operation at typical processor case temperatures up to 80-90 degrees C. It is demonstrated that increasing the temperature from room temperature to 90 degrees C leads to a predicted maximum optical gain reduction of similar to 1.26 for both materials. In addition, the predicted erbium related optical gain at significant inversion levels in samples processed at low temperature (600 degrees C) is a factor similar to 9 higher than for samples processed at high temperature (1060 degrees C). These findings demonstrate that relatively thermally stable gain performance of the Er-doped Si-rich SiO2 up to typical processor operating temperatures is possible and indicate that low-temperature-processed erbium-doped silicon-rich SiO2 is a technologically viable gain medium for use in silicon photonics. (C) 2010 Elsevier B.V. All rights reserved.