Up-Conversion Device Based on Quantum Dots With High-Conversion Efficiency Over 6%

Photoluminescence up-conversion in InAsÕGaAs self-assembled quantum dots

We report up-converted photoluminescence in a structure with InAs quantum dots embedded in GaAs. An efficient emission from the GaAs barrier is observed with resonant excitation of both the dots and the wetting layer. The intensity of the up-converted luminescence is found to increase superlinearly with the excitation density. The results suggest that the observed effect is due to a two-step tw...

Giant Up-Conversion Efficiency of InGaAs Quantum Dots in a Planar Microcavity

Self-assembled InGaAs quantum dots (QDs) were fabricated inside a planar microcavity with two vertical cavity modes. This allowed us to excite the QDs coupled to one of the vertical cavity modes through two propagating cavity modes to study their down- and up-converted photoluminescence (PL). The up-converted PL increased continuously with the increasing temperature, reaching an intensity level...

Frequency up-conversion based single photon, mid-IR spectral imaging with 20% quantum efficiency

Control over Power Conversion Efficiency of BHJ Solar Cells: Learn more from Less, with Artificial Intelligence

Harvesting the energy from the sun through the bulk heterojunction (BHJ) solar cells need materials with specific electronic characteristics. However, any promising material if cast improperly in cells will end into low or even null power conversion efficiency (PCE). Cell casting optimization is a time/material consumable step in any photovoltaic manufacturing practice. In this study, we sh...

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. A conver...