Table 1 . Optical properties of ordinary QDs .

Core composition	Excitation wavelength (nm)	Emission wavelength (nm)	Quantum yield	References
Si	320–450	480–650	0.1–0.25	23
CdS	350–470	370–500	0.34	24
CdSe	450–640	470–660	0.85	25
InP	550–650	620–1100	0.30–0.60	26
PbSe	900–4000	>1000	0.12–0.81	27