Enhanced photoluminescence of InGaAs/AlGaAs quantum well with tungsten disulfide quantum dots.

The pristine and diethylenetriamine (DETA)-doped tungsten disulfide quantum dots (WS QDs) with an average lateral size of about 5 nm have been synthesized using pulsed laser ablation (PLA). Introduction of the synthesized WS QDs on the InGaAs/AlGaAs quantum wells (QWs) can improve the photoluminescence (PL) of the InGaAs/AlGaAs QW as high as 6 fold. On the basis of the time-resolved PL and Kelvin probe measurements, the PL enhancement is attributed to the carrier transfer from the pristine or DETA-doped WS QDs to the InGaAs/AlGaAs QW.

Enhanced Conversion Efficiency of III-V Triple-junction Solar Cells with Graphene Quantum Dots.

Graphene has been used to synthesize graphene quantum dots (GQDs) via pulsed laser ablation. By depositing the synthesized GQDs on the surface of InGaP/InGaAs/Ge triple-junction solar cells, the short-circuit current, fill factor, and conversion efficiency were enhanced remarkably. As the GQD concentration is increased, the conversion efficiency in the solar cell increases accordingly.