Combining semilocal exchange with dynamical mean-field theory : Electronic structure and optical response of rare-earth sesquioxides
(2022) In Physical Review B 105(8).- Abstract
In rare-earth semiconductors, wide ligand p and rare-earth 5d bands coexist with localized, partially filled 4f shells. A simultaneous description for both extended and localized states represents a significant challenge for first-principles theories. Here, we combine an ab initio dynamical mean-field theory approach to strong local correlations with a perturbative application of the semilocal modified Becke-Johnson exchange potential to correct the semiconducting gap. We apply this method to calculate the electronic structure and optical response of the light rare-earth sesquioxides R2O3 (R=La,Ce,Pr,andNd). Our calculations correctly capture a nontrivial evolution of the optical gap in R2O3 due to a progressive lowering of the 4f... (More)
In rare-earth semiconductors, wide ligand p and rare-earth 5d bands coexist with localized, partially filled 4f shells. A simultaneous description for both extended and localized states represents a significant challenge for first-principles theories. Here, we combine an ab initio dynamical mean-field theory approach to strong local correlations with a perturbative application of the semilocal modified Becke-Johnson exchange potential to correct the semiconducting gap. We apply this method to calculate the electronic structure and optical response of the light rare-earth sesquioxides R2O3 (R=La,Ce,Pr,andNd). Our calculations correctly capture a nontrivial evolution of the optical gap in R2O3 due to a progressive lowering of the 4f states along the series and their multiplet structure. 2p-4f hybridization is found to induce a substantial upward shift for the occupied 4f states occurring within the p-d gap, thus reducing the magnitude of the optical gap. We show that a characteristic plateau observed in the optical conductivity in the Pr and Nd sesquioxides right above their absorption edge is a fingerprint of 4f states located within the p-d gap.
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- author
- Boust, James ; Galler, Anna ; Biermann, Silke LU and Pourovskii, Leonid V.
- organization
- publishing date
- 2022-02-15
- type
- Contribution to journal
- publication status
- published
- subject
- in
- Physical Review B
- volume
- 105
- issue
- 8
- article number
- 085133
- publisher
- American Physical Society
- external identifiers
-
- scopus:85126064139
- ISSN
- 2469-9950
- DOI
- 10.1103/PhysRevB.105.085133
- language
- English
- LU publication?
- yes
- id
- 05d90f49-d0bc-4556-ba94-cd92be39c881
- date added to LUP
- 2022-06-15 13:21:24
- date last changed
- 2025-04-04 15:19:57
@article{05d90f49-d0bc-4556-ba94-cd92be39c881,
abstract = {{<p>In rare-earth semiconductors, wide ligand p and rare-earth 5d bands coexist with localized, partially filled 4f shells. A simultaneous description for both extended and localized states represents a significant challenge for first-principles theories. Here, we combine an ab initio dynamical mean-field theory approach to strong local correlations with a perturbative application of the semilocal modified Becke-Johnson exchange potential to correct the semiconducting gap. We apply this method to calculate the electronic structure and optical response of the light rare-earth sesquioxides R2O3 (R=La,Ce,Pr,andNd). Our calculations correctly capture a nontrivial evolution of the optical gap in R2O3 due to a progressive lowering of the 4f states along the series and their multiplet structure. 2p-4f hybridization is found to induce a substantial upward shift for the occupied 4f states occurring within the p-d gap, thus reducing the magnitude of the optical gap. We show that a characteristic plateau observed in the optical conductivity in the Pr and Nd sesquioxides right above their absorption edge is a fingerprint of 4f states located within the p-d gap.</p>}},
author = {{Boust, James and Galler, Anna and Biermann, Silke and Pourovskii, Leonid V.}},
issn = {{2469-9950}},
language = {{eng}},
month = {{02}},
number = {{8}},
publisher = {{American Physical Society}},
series = {{Physical Review B}},
title = {{Combining semilocal exchange with dynamical mean-field theory : Electronic structure and optical response of rare-earth sesquioxides}},
url = {{http://dx.doi.org/10.1103/PhysRevB.105.085133}},
doi = {{10.1103/PhysRevB.105.085133}},
volume = {{105}},
year = {{2022}},
}