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Pseudogap and antiferromagnetic correlations in the hubbard model
Alexandru Macridin1, M Jarrell, Thomas Maier
1University of Cincinnati, Cincinnati, Ohio, 45221, USA.
Physical Review Letters
|August 16, 2006
Summary
Long-range antiferromagnetic correlations cause the pseudogap in electron-doped Hubbard models. The next-nearest neighbor hopping (t’) influences physics near (0, pi) and has minimal effect on spectra, except at the zone edge.
Area of Science:
- Condensed Matter Physics
- Quantum Many-Body Theory
- Materials Science
Background:
- The Hubbard model is a fundamental model in condensed matter physics, describing interacting electrons in solids.
- Understanding the pseudogap phenomenon in strongly correlated electron systems is crucial for explaining unconventional superconductivity.
Purpose of the Study:
- To investigate the origins of the pseudogap in the single-particle spectra of the Hubbard model with next-nearest neighbor hopping (t').
- To elucidate the roles of long-range and short-range correlations in the underdoped region.
Main Methods:
- Dynamical Cluster Approximation (DCA)
- Quantum Monte Carlo (QMC) simulations
- Calculation of single-particle spectra
Main Results:
- The pseudogap along the zone diagonal in electron-doped systems is attributed to long-range antiferromagnetic correlations.
- The parameter t' significantly impacts physics near (0, pi), driven by short-range correlations.
- The effect of t' on low-energy angle-resolved photoemission spectroscopy (ARPES) spectra is minor, except near the zone edge.
Conclusions:
- Short-range correlations are sufficient to generate a pseudogap signal in magnetic susceptibility and single-particle spectra near (pi, pi/2).
- The pseudogap location is not necessarily near the Fermi surface.
- The interplay between magnetic correlations and hopping parameters dictates the electronic properties.
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