Jump to main content
Jump to site search

Issue 48, 2017
Previous Article Next Article

Biexciton and trion energy transfer from CdSe/CdS giant nanocrystals to Si substrates

Author affiliations

Abstract

Observation of energy transfer (ET) from multiexcitonic (MX) complexes in nanocrystal quantum dots (NQDs) has been severely restricted due to efficient nonradiative Auger recombination leading to very low MX emission quantum yields. Here we employed “giant” CdSe/CdS NQDs with suppressed Auger recombination to study ET of biexcitons (BX) and charged excitons (trions) into Si substrate. Photoluminescence (PL) measurements of (sub)monolayers of gNQDs controllably assembled on various interacting surfaces and augmented by single gNQD's imaging reveal appearance of BX spectral signatures and progressive acceleration of PL lifetimes of all excitonic species on Si substrates. From statistical analysis of a large number of PL lifetime traces, representative exciton, trion and BX ET efficiencies are measured as ∼75%, 55% and 45% respectively. Detailed analysis of the MX's radiative rates demonstrate the crucial role of the radiative (waveguide) ET in maintaining high overall transfer efficiency despite the prevalent Auger recombination. Our observations point towards practical utilization of MX-bearing nanocrystals in future optoelectronics architectures.

Graphical abstract: Biexciton and trion energy transfer from CdSe/CdS giant nanocrystals to Si substrates

Back to tab navigation

Supplementary files

Publication details

The article was received on 22 Aug 2017, accepted on 29 Nov 2017 and first published on 29 Nov 2017


Article type: Paper
DOI: 10.1039/C7NR06272A
Citation: Nanoscale, 2017,9, 19398-19407
  •   Request permissions

    Biexciton and trion energy transfer from CdSe/CdS giant nanocrystals to Si substrates

    T. Guo, S. Sampat, S. M. Rupich, J. A. Hollingsworth, M. Buck, H. Htoon, Y. J. Chabal, Y. N. Gartstein and A. V. Malko, Nanoscale, 2017, 9, 19398
    DOI: 10.1039/C7NR06272A

Search articles by author

Spotlight

Advertisements