Effect of Interfacial Alloying versus “Volume Scaling” on Auger Recombination in Compositionally Graded Semiconductor Quantum Dots

• DOI: 10.1021/acs.nanolett.7b02438
• Publication Date: 2017-07-27T10:25:55Z
• Authors: Young-Shin Park; Jaehoon Lim; Nikolay S. Makarov; Victor I. Klimov
• Keywords: Auger effect

Auger recombination is a nonradiative three-particle process wherein the electron-hole energy dissipates as kinetic of third carrier. decay enhanced in quantum-dot (QD) forms semiconductor materials compared to their bulk counterparts. Because this detrimental many prospective applications QDs, development effective approaches for suppressing has been an important goal QD field. One such approach involves "smoothing" confinement potential, which suppresses intraband transition involved dissipation energy. The present study evaluates effect increasing "smoothness" potential on employing series CdSe/CdS-based QDs core and shell are separated by intermediate layer CdSexS1-x alloy comprised 1-5 sublayers with radially tuned composition. As inferred from single-dot measurements, use five-step grading scheme allows strong suppression both biexcitons charged excitons. Further, due nearly identical emissivities neutral excitons, these exhibit interesting phenomenon lifetime blinking random fluctuations photoluminescence occur constant emission intensity.