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Updated: Jul 12, 2026
05:39
Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Dynamics of Superconducting Pairs in the Two-Dimensional Hubbard Model
G Sordi1, E M O'Callaghan1, C Walsh1
1Royal Holloway, University of London, Department of Physics, Egham, Surrey, United Kingdom, TW20 0EX.
Physical Review Letters
|July 10, 2026
Summary
Superconducting correlations in cuprates arise from low-frequency pair-forming processes driven by superexchange interactions, not high interaction strengths. This clarifies the pairing mechanism in these materials.
Area of Science:
- Condensed Matter Physics
- Materials Science
Background:
- Superconducting correlations in cuprates offer insights into the underlying pairing mechanisms.
- Understanding these mechanisms is crucial for developing novel superconducting materials.
Purpose of the Study:
- To conduct an exhaustive study of superconducting correlations in the two-dimensional Hubbard model.
- To quantify the dependence of the superconducting gap and d-wave pairing frequency scales on doping (δ) and interaction strength (U).
Main Methods:
- Utilized cellular dynamical mean-field theory (CDMFT) for an in-depth analysis.
- Systematically investigated the impact of varying doping levels and interaction strengths.
Main Results:
- Identified pair-forming processes confined to frequencies determined by the superexchange interaction.
- Found pair-breaking processes occurring at higher frequencies.
- Ruled out pair-forming and pair-breaking processes occurring on the scale of the interaction strength (U).
Conclusions:
- The interaction strength (U) is effectively screened at high frequencies by d-wave pairing.
- At low frequencies, U generates the superexchange interaction, which drives the dominant pair-forming processes contributing to superconductivity.
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