Symmetry breaking induced activation of the nanocrystal photoluminescence

Efros, Alexander
2017-05
Thumbnail Image

View/Download File

Efros_MinnesotaMay4-2017AR.pdf (842.38 KB)

Persistent link to this item

https://hdl.handle.net/11299/188312
Statistics
View Statistics

Journal Title

Journal ISSN

Volume Title

Title

Symmetry breaking induced activation of the nanocrystal photoluminescence

Authors

Published Date

2017-05

Publisher

Type

Presentation

Abstract

We have shown that the descent of the nanocrystal symmetry from spherical to point group Cs, which is characterized by just one mirror plane symmetry element, leads step by step to activation of all five F =2, Fz= 2,1, 0 excitons. Even the ground exciton becomes optically active, which should be observable in low-temperature photoluminescence measurements. For several intermediate symmetries the band edge exciton fine structure consists of sets of three linearly polarized mutually orthogonal dipoles plus a dark exciton, one of which is always the ground state. We quantify the effect of symmetry descent on the exciton fine structure by introducing a charged Coulomb impurity in the nanocrystals. The calculations show that the nanocrystal symmetry breaking by a Coulomb impurity, particularly a positively charged center, shortens the radiative decay of nanocrystals even at room temperatures in qualitative agreement with the increase in PL efficiency observed in nanocrystals doped with positive Ag charge centers.

Keywords

Description

Related to

Replaces

License

Collections

Charge and Energy Transport in Nanocrystal Assemblies (CETNA) 2017

Series/Report Number

Funding information

Isbn identifier

Doi identifier

Previously Published Citation

Suggested citation

Efros, Alexander. (2017). Symmetry breaking induced activation of the nanocrystal photoluminescence. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/188312.

Content distributed via the University Digital Conservancy may be subject to additional license and use restrictions applied by the depositor. By using these files, users agree to the Terms of Use. Materials in the UDC may contain content that is disturbing and/or harmful. For more information, please see our statement on harmful content in digital repositories.