Morphology-Dependent One- and Two-Photon Absorption Properties in Blue Emitting CsPbBr₃Nanocrystals

Summary, in English

The linear and nonlinear optical parameters and morphologic dependence of CsPbBr3 nanocrystals (NCs) are crucial for device engineering. In particular, such information in asymmetric nanocrystals is still insufficient. We characterized the OPLA (σ1) and TPA cross sections (σ2) of a series CsPbBr3 nanocrystals with various aspect ratios (AR) using femtosecond transient absorption spectroscopy (TAS). The σ1 presents a linear volume dependence of all the samples, which agrees with the previous behavior in CsPbBr3 QDs. However, the σ2 values do not exhibit conventional power dependency of the crystal volume but are also modulated by the shape-dependent local field factors. In addition, the local field effect in CsPbBr3 NCs is contributed by their asymmetric morphologies and polar ionic lattices, which is more pronounced than in conventional semiconductor NCs. Finally, we revealed that the lifetimes of photogenerated multiexcitonic species of those nanocrystals feature identical morphology independence in both OPLA and TPA.

• Author: Sol Laura Gutierrez Alvarez; Christina Basse Riel; Mahtab Madani; Mohamed Abdellah; Qian Zhao; Xianshao Zou; Tönu Pullerits; Kaibo Zheng
• Department/s: LTH Profile Area: Nanoscience and Semiconductor Technology; Chemical Physics; NanoLund: Centre for Nanoscience; LTH Profile Area: Photon Science and Technology
• Publishing year: 2022
• Language: English
• Pages: 4897-4904
• Publication/Series: Journal of Physical Chemistry Letters
• Volume: 13
• Issue: 22
• Links: http://dx.doi.org/10.1021/acs.jpclett.2c00710
• Document type: Journal article
• Publisher: The American Chemical Society (ACS)
• Topic: Atom and Molecular Physics and Optics
• Status: Published
• ISBN/ISSN/Other: ISSN: 1948-7185