Highly efficient, spatially coherent distributed feedback lasers from dense colloidal quantum dot films

• Main Authors: Dang, Cuong, Lee, Joonhee, Roh, Kwangdong, Kim, Hanbit, Ahn, Sungmo, Jeon, Heonsu, Breen, Craig, Steekel, Jonathan S., Coe-Sullivan, Seth, Nurmikko, Arto
• Other Authors: School of Electrical and Electronic Engineering
• Format: Article
• Language: English
• Published: 2014
• Subjects: DRNTU::Engineering::Electrical and electronic engineering
• Online Access: https://hdl.handle.net/10356/79635; http://hdl.handle.net/10220/19581
• Institution: Nanyang Technological University

Colloidal quantum dots (CQD) are now making their entry to full-color displays, endowed by their brightness and single-material base. By contrast, many obstacles have been encountered in their use towards lasers. We demonstrate here optically pumped distributed feedback (DFB) lasers, based on close-packed, solid films self-assembled from type-I CQDs. Notably, the single mode CQD-DFB lasers could reach such a low threshold as to be pumpable with a compact pulsed source in a quasi-continuous wave regime. Our results show the spatially and temporally coherent laser beam outputs with power of 400 μW and a quantum efficiency of 32%.