Two-band optical gain and ultrabright electroluminescence from colloidal quantum dots at 1000 A cm^-2.

ABSTRACT: Colloidal quantum dots (QDs) are attractive materials for the realization of solution-processable laser diodes. Primary challenges towards this objective are fast optical-gain relaxation due to nonradiative Auger recombination and poor stability of colloidal QD solids under high current densities required to obtain optical gain. Here we resolve these challenges and achieve broad-band optical gain spanning the band-edge (1S) and the higher-energy (1P) transitions. This demonstration is enabled by continuously graded QDs with strongly suppressed Auger recombination and a current-focusing device design, combined with short-pulse pumping. Using this approach, we achieve ultra-high current densities (~1000 A cm^-2) and brightness (~10 million cd m^-2), and demonstrate an unu

SUBMITTER: Jung H 

PROVIDER: S-EPMC9243032 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature