Band structure engineering via piezoelectric fields in strained anisotropic CdSe/CdS nanocrystals
Articolo
Data di Pubblicazione:
2015
Citazione:
Band structure engineering via piezoelectric fields in strained anisotropic CdSe/CdS nanocrystals / S. Christodoulou, F. Rajadell, A. Casu, G. Vaccaro, J.Q. Grim, A. Genovese, L. Manna, J.I. Climente, F. Meinardi, G. Raino, T. Stoferle, R.F. Mahrt, J. Planelles, S. Brovelli, I. Moreels. - In: NATURE COMMUNICATIONS. - ISSN 2041-1723. - 6:1(2015 Jul), pp. 7905.1-7905.8. [10.1038/ncomms8905]
Abstract:
Strain in colloidal heteronanocrystals with non-centrosymmetric lattices presents a unique opportunity for controlling optoelectronic properties and adds a new degree of freedom to existing wavefunction engineering and doping paradigms. We synthesized wurtzite CdSe nanorods embedded in a thick CdS shell, hereby exploiting the large lattice mismatch between the two domains to generate a compressive strain of the CdSe core and a strong piezoelectric potential along its c-axis. Efficient charge separation results in an indirect ground-state transition with a lifetime of several microseconds, almost one order of magnitude longer than any other CdSe/CdS nanocrystal. Higher excited states recombine radiatively in the nanosecond time range, due to increasingly overlapping excited-state orbitals. k? p calculations confirm the importance of the anisotropic shape and crystal structure in the buildup of the piezoelectric potential. Strain engineering thus presents an efficient approach to highly tunable single- and multiexciton interactions, driven by a dedicated core/shell nanocrystal design.
Tipologia IRIS:
01 - Articolo su periodico
Elenco autori:
S. Christodoulou, F. Rajadell, A. Casu, G. Vaccaro, J.Q. Grim, A. Genovese, L. Manna, J.I. Climente, F. Meinardi, G. Raino, T. Stoferle, R.F. Mahrt, J. Planelles, S. Brovelli, I. Moreels
Link alla scheda completa:
Link al Full Text: