High efficiency and nearly cubic power dependence of below-band-edge photoluminescence in water-soluble, copper-doped ZnSe/ZnS quantum dots

Opt Express. 2008 Apr 14;16(8):5710-5. doi: 10.1364/oe.16.005715.

Abstract

Three-photon absorption (3PA) and three-photon-excited photoluminescence (3PE-PL) of ZnSe/ZnS and copper-doped ZnSe/ZnS core-shell quantum dots (QDs) in aqueous solutions have been unambiguously determined by Z-scan and 3PE-PL measurements with 200-fs laser pulses at 1000 nm. The 3PA cross-section is as high as 3.5 x 10(-77) cm6 s2 photon(-2) for 4.1 nm-sized, copper-doped ZnSe/ZnS QDs, while their below-band-edge PL is found to be nearly cubic dependent on the excitation intensity, with efficiency enhanced by approximately 20 fold compared to the undoped ZnSe/ZnS QDs.

MeSH terms

  • Computer Simulation
  • Computer-Aided Design
  • Copper / chemistry*
  • Equipment Design
  • Equipment Failure Analysis
  • Luminescent Measurements / instrumentation*
  • Models, Theoretical*
  • Quantum Dots*
  • Selenium Compounds / chemistry*
  • Selenium Compounds / radiation effects
  • Sensitivity and Specificity
  • Sulfides / chemistry*
  • Sulfides / radiation effects
  • Water / chemistry*
  • Zinc Compounds / chemistry*
  • Zinc Compounds / radiation effects

Substances

  • Selenium Compounds
  • Sulfides
  • Zinc Compounds
  • Water
  • Copper
  • zinc sulfide
  • zinc selenide