Advanced search
1 file | 2.92 MB Add to list

Exciton fine structure and lattice dynamics in InP/ZnSe core/shell quantum dots

(2018) ACS PHOTONICS. 5(8). p.3353-3362
Author
Organization
Abstract
Nanocrystalline InP quantum dots (QDs) hold promise for heavy-metal-free optoelectronic applications due to their bright and size tunable emission in the visible range. Photochemical stability and high photoluminescence (PL) quantum yield are obtained by a diversity of epitaxial shells around the InP core. To understand and optimize the emission line shapes, the exciton fine structure of InP core/shell QD systems needs be investigated. Here, we study the exciton fine structure of InP/ZnSe core/shell QDs with core diameters ranging from 2.9 to 3.6 nm (PL peak from 2.3 to 1.95 eV at 4 K). PL decay measurements as a function of temperature in the 10 mK to 300 K range show that the lowest exciton fine structure state is a dark state, from which radiative recombination is assisted by coupling to confined acoustic phonons with energies ranging from 4 to 7 meV, depending on the core diameter. Circularly polarized fluorescence line-narrowing (FLN) spectroscopy at 4 K under high magnetic fields (up to 30 T) demonstrates that radiative recombination from the dark F = +/- 2 state involves acoustic and optical phonons, from both the InP core and the ZnSe shell. Our data indicate that the highest intensity FLN peak is an acoustic phonon replica rather than a zero-phonon line, implying that the energy separation observed between the F = +/- 1 state and the highest intensity peak in the FLN spectra (6 to 16 meV, depending on the InP core size) is larger than the splitting between the dark and bright fine structure exciton states.
Keywords
exciton fine structure, InP/ZnSe core/shell quantum dots, acoustic and optical phonons, high magnetic field, BAND-EDGE EXCITON, SEMICONDUCTOR NANOCRYSTALS, NONCOORDINATING SOLVENT, CDSE NANOCRYSTALS, INP NANOCRYSTALS, EMISSION, DISPLAYS, BLINKING, BRIGHT, LIGHT

Downloads

  • ACSPhot 2018 5 3353.pdf
    • full text
    • |
    • open access
    • |
    • PDF
    • |
    • 2.92 MB

Citation

Please use this url to cite or link to this publication:

MLA
Brodu, Annalisa, et al. “Exciton Fine Structure and Lattice Dynamics in InP/ZnSe Core/Shell Quantum Dots.” ACS PHOTONICS, vol. 5, no. 8, 2018, pp. 3353–62.
APA
Brodu, A., Ballottin, M. V., Buhot, J., van Harten, E. J., Dupont, D., La Porta, A., … Vanmaekelbergh, D. (2018). Exciton fine structure and lattice dynamics in InP/ZnSe core/shell quantum dots. ACS PHOTONICS, 5(8), 3353–3362.
Chicago author-date
Brodu, Annalisa, Mariana V Ballottin, Jonathan Buhot, Elleke J van Harten, Dorian Dupont, Andrea La Porta, P Tim Prins, et al. 2018. “Exciton Fine Structure and Lattice Dynamics in InP/ZnSe Core/Shell Quantum Dots.” ACS PHOTONICS 5 (8): 3353–62.
Chicago author-date (all authors)
Brodu, Annalisa, Mariana V Ballottin, Jonathan Buhot, Elleke J van Harten, Dorian Dupont, Andrea La Porta, P Tim Prins, Mickaël Tessier, Marijn AM Versteegh, Val Zwiller, Sara Bals, Zeger Hens, Freddy T Rabouw, Peter CM Christianen, Celso de Mello Donega, and Daniel Vanmaekelbergh. 2018. “Exciton Fine Structure and Lattice Dynamics in InP/ZnSe Core/Shell Quantum Dots.” ACS PHOTONICS 5 (8): 3353–3362.
Vancouver
1.
Brodu A, Ballottin MV, Buhot J, van Harten EJ, Dupont D, La Porta A, et al. Exciton fine structure and lattice dynamics in InP/ZnSe core/shell quantum dots. ACS PHOTONICS. 2018;5(8):3353–62.
IEEE
[1]
A. Brodu et al., “Exciton fine structure and lattice dynamics in InP/ZnSe core/shell quantum dots,” ACS PHOTONICS, vol. 5, no. 8, pp. 3353–3362, 2018.
@article{8637755,
  abstract     = {Nanocrystalline InP quantum dots (QDs) hold promise for heavy-metal-free optoelectronic applications due to their bright and size tunable emission in the visible range. Photochemical stability and high photoluminescence (PL) quantum yield are obtained by a diversity of epitaxial shells around the InP core. To understand and optimize the emission line shapes, the exciton fine structure of InP core/shell QD systems needs be investigated. Here, we study the exciton fine structure of InP/ZnSe core/shell QDs with core diameters ranging from 2.9 to 3.6 nm (PL peak from 2.3 to 1.95 eV at 4 K). PL decay measurements as a function of temperature in the 10 mK to 300 K range show that the lowest exciton fine structure state is a dark state, from which radiative recombination is assisted by coupling to confined acoustic phonons with energies ranging from 4 to 7 meV, depending on the core diameter. Circularly polarized fluorescence line-narrowing (FLN) spectroscopy at 4 K under high magnetic fields (up to 30 T) demonstrates that radiative recombination from the dark F = +/- 2 state involves acoustic and optical phonons, from both the InP core and the ZnSe shell. Our data indicate that the highest intensity FLN peak is an acoustic phonon replica rather than a zero-phonon line, implying that the energy separation observed between the F = +/- 1 state and the highest intensity peak in the FLN spectra (6 to 16 meV, depending on the InP core size) is larger than the splitting between the dark and bright fine structure exciton states.},
  author       = {Brodu, Annalisa and Ballottin, Mariana V and Buhot, Jonathan and van Harten, Elleke J and Dupont, Dorian and La Porta, Andrea and Prins, P Tim and Tessier, Mickaël and Versteegh, Marijn AM and Zwiller, Val and Bals, Sara and Hens, Zeger and Rabouw, Freddy T and Christianen, Peter CM and de Mello Donega, Celso and Vanmaekelbergh, Daniel},
  issn         = {2330-4022},
  journal      = {ACS PHOTONICS},
  keywords     = {exciton fine structure,InP/ZnSe core/shell quantum dots,acoustic and optical phonons,high magnetic field,BAND-EDGE EXCITON,SEMICONDUCTOR NANOCRYSTALS,NONCOORDINATING SOLVENT,CDSE NANOCRYSTALS,INP NANOCRYSTALS,EMISSION,DISPLAYS,BLINKING,BRIGHT,LIGHT},
  language     = {eng},
  number       = {8},
  pages        = {3353--3362},
  title        = {Exciton fine structure and lattice dynamics in InP/ZnSe core/shell quantum dots},
  url          = {http://dx.doi.org/10.1021/acsphotonics.8b00615},
  volume       = {5},
  year         = {2018},
}

Altmetric
View in Altmetric
Web of Science
Times cited: