Multiexcitonic dual emission in CdSe/CdS tetrapods and nanorods.
CdSe/CdS semiconductor nanocrystal heterostructures are currently of high interest for the peculiar electronic structure offering unique optical properties. Here, we show that nanorods and tetrapods made of such material combination enable efficient multiexcitonic emission, when the volume of the nanoparticle is maximized. This condition is fulfilled by tetrapods with an arm length of 55 nm and results in a dual emission with comparable intensities from the CdS arms and CdSe core. The relative intensities of the dual emission, originating from exciton phase-space filling and reduced Auger recombination, can be effectively modulated by the photon fluence of the pump laser. The results, obtained under steady-state detection conditions, highlight the properties of tetrapods as multiexciton dual-color emitters.
Photonics and Optoelectronics Group, Department of Physics and CeNS, Ludwig-Maximilians-Universität, D-80799, Munich, Germany.
Andrey A
AA
Lutich
Christian
C
Mauser
Enrico
E
Da Como
Jing
J
Huang
Aleksandar
A
Vaneski
Dmitri V
DV
Talapin
Andrey L
AL
Rogach
Jochen
J
Feldmann
D019187:Cadmium Compounds / Q000737:chemistry*; D008029:Lighting / Q000379:methods*; D008422:Materials Testing; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D013440:Sulfides / Q000737:chemistry*
D019187:Cadmium Compounds; D018036:Selenium Compounds; D013440:Sulfides; C034939:cadmium sulfide; C058667:cadmium selenide