High efficiency silicon nanodisk laser based on colloidal CdSe/ZnS QDs
نویسندگان
چکیده
INTRODUCTION Using colloidal CdSe/ZnS quantum dots in the submicron-sized silicon disk cavity, we have developed a visible wavelength nanodisk laser that operates under extremely low threshold power at room temperature. METHODS Time-resolved photoluminescence (PL) of QDs; nanodisk by e-beam lithography. RESULTS Observation of lasing action at 594 nm wavelength for quantum dots on a nanodisk (750 nm in diameter) cavity and an ultra-low threshold of 2.8 µW. CONCLUSION From QD concentration dependence studies we achieved nearly sevenfold increase in spontaneous emission (SE) rate. We have achieved high efficient and high SE coupling rate in such a QD nanodisk laser.
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