Thermally stimulated exciton emission in Si nanocrystals  

作　　者：Elinore MLD de Jong Huub Rutjes Jan Valenta M Tuan Trinh Alexander N Poddubny Irina N Yassievich Antonio Capretti Tom Gregorkiewicz 

机构地区：[1]Van der Waals-Zeeman Institute,University of Amsterdam,Science Park 904,1098 XH,Amsterdam,The Netherlands [2]Department of Chemical Physics and Optics,Faculty of Mathematics and Physics,Charles University,Ke Karlovu 3,12116 Prague 2,Czech Republic [3]Department of Electrical Engineering and Computer Science,University of Michigan,2200 Bonisteel Blvd,Ann Arbor,MI 48109,USA [4]Ioffe Institute,Russian Academy of Sciences,26 Polytechnicheskaya,194021 St Petersburg,Russia

出　　处：《Light(Science & Applications)》2017年第1期228-234,共7页光（科学与应用)（英文版）

基　　金：supported by the Dutch Technology Foundation STW,which is part of the Netherlands Organisation for Scientific Research(NWO);funded by the Ministry of Economic Affairs;support within the framework of the Czech-German collaborative project,16-09745J(DFT-GACR);supported by the Russian Science Foundation,Grant No.14-12-01067。

摘　　要：Increasing temperature is known to quench the excitonic emission of bulk silicon,which is due to thermally induced dissociation of excitons.Here,we demonstrate that the effect of temperature on the excitonic emission is reversed for quantumconfined silicon nanocrystals.Using laser-induced heating of silicon nanocrystals embedded in SiO2,we achieved a more than threefold(4300%)increase in the radiative(photon)emission rate.We theoretically modeled the observed enhancement in terms of the thermally stimulated effect,taking into account the massive phonon production under intense illumination.These results elucidate one more important advantage of silicon nanostructures,illustrating that their optical properties can be influenced by temperature.They also provide an important insight into the mechanisms of energy conversion and dissipation in ensembles of silicon nanocrystals in solid matrices.In practice,the radiative rate enhancement under strong continuous wave optical pumping is relevant for the possible application of silicon nanocrystals for spectral conversion layers in concentrator photovoltaics.

关 键 词：MICRO-PHOTOLUMINESCENCE nanocrystal optical spectroscopy SILICON THERMAL 

分 类 号：TB3[一般工业技术—材料科学与工程]