DSpace Arşivi :: by Yazar "Li, Quyang" değerine göre listeleniyor

Listeleniyor 1 - 1 / 1

High-efficiency optical gain in Type-II semiconductor nanocrystals of alloyed colloidal quantum wells
(Amer Chemical Soc, 2017) Güzeltürk, Burak; Keleştemur, Yusuf; Olutaş, Murat; Li, Quyang; Lian, Tianquan
Colloidal nanocrystals having controlled size, tailored shape, and tuned composition have been explored for optical gain and lasing. Among these, nanocrystals having Type-II electronic structure have been introduced toward low-threshold gain. However, to date, their performance has remained severely limited due to diminishing oscillator strength and modest absorption cross-section. Overcoming these problems, here we realize highly efficient optical gain in Type-II nanocrystals by using alloyed colloidal quantum wells. With composition-tuned core/alloyed-crown CdSe/CdSexTe1-x quantum wells, we achieved amplified spontaneous emission thresholds as low as 26 mu J/cm(2), long optical gain lifetimes (tau(gain) approximate to 400 ps), and high modal gain coefficients (g(modal) approximate to 930 cm(-1)). We uncover that the optical gain in these Type-II quantum wells arises from the excitations localized to the alloyed-crown region that are electronically coupled to the charge-transfer state. These alloyed heteronanostructures exhibiting remarkable optical gain performance are expected to be highly appealing for future display and lighting technologies.