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Pseudogap temperature as a Widom line in doped Mott insulators
1Theory Group, Institut Laue Langevin, 6 Rue Jules Horowitz, 38042 Grenoble Cedex, France. sordi@ill.fr
Scientific Reports
|August 3, 2012
Summary
The pseudogap temperature (T*) in superconductors arises from strong coupling, not broken symmetry. This characteristic temperature marks a crossover along the Widom line, explaining the pseudogap phase diagram.
Area of Science:
- Condensed Matter Physics
- Quantum Materials Science
Background:
- The pseudogap is an unusual state in hole-doped high-temperature superconductors below temperature T*.
- Understanding the origin of T* is crucial for high-temperature superconductivity research.
Purpose of the Study:
- To investigate if strong coupling and short nonlocal correlations in the Hubbard model can solely cause the pseudogap.
- To determine the role of thermodynamic anomalies and phase transitions in the pseudogap phenomenon.
Main Methods:
- Utilizing cluster dynamical mean-field theory (CDMFT).
- Analyzing the simplest correlated electron model: the Hubbard model.
Main Results:
- The pseudogap temperature T* is identified as a sharp crossover between dynamical regimes.
- This crossover occurs along a line of thermodynamic anomalies situated above a first-order phase transition (Widom line).
- The Widom line acts as the organizing principle for the cuprate pseudogap phase diagram.
Conclusions:
- Strong coupling physics and short nonlocal correlations are sufficient to explain the pseudogap.
- No additional broken symmetry is required; broken symmetries emerge within the pseudogap state.
- The Widom line provides a new framework for understanding the pseudogap phase in cuprates.
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