Related Experiment Video
Updated: Oct 18, 2025
06:44
Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
3.4K
Oxygen hole content, charge-transfer gap, covalency, and cuprate superconductivity.
Nicolas Kowalski1,2,3, Sidhartha Shankar Dash1,2,3, Patrick Sémon1,3
1Département de physique, Université de Sherbrooke, Sherbrooke, QC J1K 2R1, Canada.
Summary
High transition temperatures in cuprate superconductors correlate with oxygen hole content. Covalency and a charge-transfer gap explain superexchange interactions, leading to superconductivity in these materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Chemistry
Background:
- Cuprate superconductors exhibit a correlation between high transition temperatures and oxygen hole content.
- A large charge-transfer gap is experimentally found to be detrimental to superconductivity in these materials.
Purpose of the Study:
- To theoretically investigate the relationship between oxygen hole content, charge-transfer gap, and superconductivity in cuprates.
- To explain experimental observations using a microscopic model.
Main Methods:
- Solving the three-band Hubbard model using cellular dynamical mean-field theory (CDMFT).
- Analyzing the role of covalency and charge-transfer gap in the electronic structure.
Main Results:
- The study demonstrates that the observed experimental trends regarding transition temperature and oxygen hole content emerge from the three-band Hubbard model.
- It is shown that covalency and a charge-transfer gap are crucial for establishing an effective superexchange interaction.
Conclusions:
- The findings are consistent with experimental evidence suggesting superexchange as the origin of cuprate superconductivity.
- The model successfully explains how covalency and charge-transfer gap contribute to pairing and superconductivity in cuprates.
Keywords:
cuprate superconductorsdynamical mean-field theoryoptimization of transition temperaturepairing mechanismthree-band Hubbard modelMore Related Videos
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