Observation of optical gain in solutions of CdS quantum dots at room temperature in the blue region

TitleObservation of optical gain in solutions of CdS quantum dots at room temperature in the blue region
Publication TypeJournal Article
Year of Publication2006
AuthorsDarugar, Q, Qian, W, EL-Sayed, MA
JournalApplied Physics Letters
Volume88
Date PublishedJun
ISBN Number0003-6951
Accession NumberWOS:000238717200008
Abstract

The optical gain dynamics has been studied for two CdS quantum dot samples dispersed in toluene at room temperature. This was carried out by using femtosecond transient absorption technique with an excitation at 400 nm and gain measurement was studied at the fluorescence maxima (440 and 460 nm). The optical gain lifetime was found to be as long as 20 ps under pump fluence as low as 0.77 mJ/cm(2). The low threshold is the result of long lifetime of electrons and holes and narrow emission bandwidth. These results suggest that CdS quantum dots in solution are excellent gain media for optically pumped high power blue lasers.

DOI10.1063/1.2217138