Edge-Emitting Silicon Nanocrystal Distributed Feedback Laser with Extremely Low Exciton Threshold

• DOI: 10.1021/acsphotonics.0c01846
• Publication Date: 2021-04-14T23:56:55Z
• Authors: Pan Zeng; Feilong Wang; Yuchen Zhang; Wenjie Zhou; Zhihe Guo; Xiang Wu; Ming Lu; Shuyu Zhang
• Keywords: Auger effect

The successful integration of a laser into the silicon photonic chip has long been holy grail photonics. Among various methods addressing this challenge, nanocrystal (Si NC) lasers remain tempting but debated topic due to their complex carrier recombination process. Here we demonstrate an optically pumped edge-emitting first-order distributed feedback Si NC by utilizing versatile nanoimprint lithography method incorporating composite working stamp. Upon femtosecond pulsed pumping, find that lasing threshold in exciton number per down 0.021 is unusually low compared with other quantum dot gain materials. To understand interesting behavior, have performed systematic transient spectrum experiments on its photoluminescence and absorption aimed at revealing role self-trapping states Our results suggest such well passivated NCs can be regarded as metastable intercept hot electrons time delay, release them back conduction band, acting like electron reservoirs continuously feed active state upper levels. In perspective, conclude surface benefit buildup population inversion lead inhibition Auger process they temporarily localize outside core verified our conclusion numerical experimental results, respectively. provide critical information processes related will aid attempts on-chip.