Fig. 3From: Design of Strain-Engineered GeSn/GeSiSn Quantum Dots for Mid-IR Direct Bandgap Emission on Si SubstrateDirectness parameter (GSL-GSΓ) variation as a function of the Ge0.72Sn0.28 QD size and Sn composition of the Ge0.65-xSi0.35Sn x surrounding layer. The dotted line indicates the thermal energy at room temperature. The inset represents a schematic definition of the directness parameterBack to article page