Low‐Threshold Organic Semiconductor Lasers with the Aid of Phosphorescent Ir(III) Complexes as Triplet Sensitizers. (20th March 2019)

• Record Type: Journal Article
• Authors: Jiang, Yi; Lv, Peng; Pan, Jin‐Qiang; Li, Yan; Lin, He; Zhang, Xin‐Wen; Wang, Jiong; Liu, Yuan‐Yuan; Wei, Qi; Xing, Gui‐Chuan; Lai, Wen‐Yong; Huang, Wei
• Is Part Of: Advanced functional materials. Volume 29:Number 19(2019)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2019-03-20
• Subjects: Förster resonance energy transfer (FRET) -- organic gain media -- organic semiconductor lasers (OSLs) -- phosphorescent Ir(III) complexes -- triplet sensitizers; Materials -- Periodicals; Chemical vapor deposition -- Periodicals; 620.11
• DOI: 10.1002/adfm.201806719
• Languages: English
• ISSNs: 1616-301X

Abstract

Abstract: Organic semiconductor lasers (OSLs) have emerged as particularly challenging. One of the major issues preventing the successful realization of lasing from organic emitters under electrically pumped conditions is the inevitable population of triplet excitons. Herein, a novel concept is presented to construct triplet–singlet guest–host gain systems with incorporating iridium complexes as the triplet sensitizers and a fluorescent conjugated polymer as the gain media to achieve light amplification. The direct triplet–singlet energy transfer process is confirmed by photoluminescence excitation spectra, photoinduced absorption spectroscopy, and fluorescence transients of the blend samples. Successful light amplification with a threefold lower amplified spontaneous emission threshold and much better lasing performance is demonstrated for the resulting triplet–singlet guest–host system as compared with the corresponding gain system without triplet sensitizers. Moreover, under electrically driven conditions, the fluorescent organic light‐emitting diodes (OLEDs) based on the triplet–singlet guest–host systems with "triplet sensitizers" exhibit enhanced electrical performance relative to those without. The work suggests an effective general methodology to utilize both the singlet and triplet excitons to contribute to the light amplification with excellent electrical performance in OLEDs, opening prospects toward attempting electrically pumped OSLs. Abstract : An effective general methodology to utilize triplet excitons to contribute to light amplification with excellent electrical performance is presented. The triplet energy is managed by converting triplet excitons to singlet excitons via Förster energy transfer. This methodology is believed to be beneficial for addressing the challenges toward attempting electrically driven organic semiconductor laser diodes.