Department of Electrical and Computer Engineering, University of Delaware, 140 Evans Hall, Newark, Delaware 19716, USA.
Opt Lett. 2010 Jul 1;35(13):2182-4. doi: 10.1364/OL.35.002182.
We study the mitigation of Si nanocrystal (Si-nc) free carrier absorption (FCA) loss at telecom wavelengths in a concentric microdisk design. The concentric microdisk design relies on using the Si-nc emission as an optical pump for the surrounding Er-based lasing media without subjecting the lasing mode to the FCA loss present in the Si-ncs. We analyze the FCA loss as a function of overhang width in this design and show that for large enough overhang width the FCA loss is negligible. We also compute the FCA cross section from the FCA loss and number of excited Si-ncs, modeled by a four-level system, and show sigma(FCA)=1.08 +/- 2.3 x 10(-17) cm(2), which is in good agreement with reported cross sections for similar films.
我们研究了在同心微盘设计中减轻硅纳米晶体（Si-nc）自由载流子吸收（FCA）损耗在电信波长下的方法。同心微盘设计依赖于使用 Si-nc 发射作为光学泵浦，为周围的基于 Er 的激光介质提供能量，而不会使激光模式受到 Si-ncs 中存在的 FCA 损耗的影响。我们分析了这种设计中悬垂宽度对 FCA 损耗的影响，并表明对于足够大的悬垂宽度，FCA 损耗可以忽略不计。我们还从 FCA 损耗和受激 Si-nc 的数量计算了 FCA 截面，受激 Si-nc 的数量由四能级系统建模，并显示 sigma(FCA)=1.08 +/- 2.3 x 10(-17) cm(2)，这与类似薄膜报道的截面非常吻合。
