Please use this identifier to cite or link to this item: https://hdl.handle.net/10356/151090
Title: Calculation of two-photon absorption by nanocrystals of CsPbBr3
Authors: Blundell, S. A.
Nguyen, T. P. T.
Guet, Claude
Keywords: Science::Physics
Issue Date: 2021
Source: Blundell, S. A., Nguyen, T. P. T. & Guet, C. (2021). Calculation of two-photon absorption by nanocrystals of CsPbBr3. Physical Review B, 103(4), 045415-. https://dx.doi.org/10.1103/PhysRevB.103.045415
Project: NRF-CRP14-2014-03 
Journal: Physical Review B 
Abstract: We present calculations of the two-photon absorption cross section σ(2)(ω) for nanocrystals (NCs) of the inorganic perovskite CsPbBr3 for photon energies ω ranging from the absorption threshold at 2ω≈2.3eV up to 2ω=3.1eV. The calculations employ a 4×4k⋅p envelope-function model, with final-state excitons described in a self-consistent Hartree-Fock approximation. The k⋅p corrections to σ(2)(ω) are found to be rather large, giving a reduction of about 30% in the cross section at the largest energies considered. The cross section is shown to be independent of polarization in the effective-mass approximation (EMA), but including k⋅p corrections leads to a small difference in σ(2)(ω) between circular and linear polarization, which rises to about 16% at 2ω=3.1eV. The theoretical cross section follows closely a power-law dependence on NC size, σ(2)(ω)∝Lα, with theoretical exponents α=3.4 (EMA) or α=3.2 (4×4k⋅p model), in excellent agreement with experiment. The dominant contribution to the exponent α is shown to be the number of final-state excitons per unit energy. Measured values of the absolute (normalized) cross section σ(2)(ω) show a large spread of values, differing by as much as a factor of 25 for some NC sizes. Our calculations strongly favor a group of measurements at the lower end of the reported range of σ(2)(ω).
URI: https://hdl.handle.net/10356/151090
ISSN: 2469-9950
DOI: 10.1103/PhysRevB.103.045415
Rights: © 2021 American Physical Society (APS). All rights reserved. This paper was published in Physical Review B and is made available with permission of American Physical Society (APS).
Fulltext Permission: open
Fulltext Availability: With Fulltext
Appears in Collections:ERI@N Journal Articles

Files in This Item:
File Description SizeFormat 
PhysRevB.103.045415.pdf792.73 kBAdobe PDFThumbnail
View/Open

Page view(s)

70
Updated on Oct 20, 2021

Download(s)

7
Updated on Oct 20, 2021

Google ScholarTM

Check

Altmetric


Plumx

Items in DR-NTU are protected by copyright, with all rights reserved, unless otherwise indicated.