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Marginal fermi liquid theory in the Hubbard model
1Max-Planck-Institut für Physik komplexer Systeme, Nöthnitzer Str. 38, D-01187 Dresden, Germany.
Physical Review Letters
|May 21, 2005
Summary
We found marginal-Fermi-liquid (MFL) behavior in the Hubbard model, with a doping-dependent Fermi surface and a phase transition to Fermi-liquid behavior. This transition is linked to the collapse of the lower Hubbard band.
Area of Science:
- Condensed matter physics
- Solid-state physics
- Computational physics
Background:
- The Hubbard model is a fundamental model for understanding strongly correlated electron systems.
- Investigating the normal state properties of the Hubbard model is crucial for explaining phenomena in materials like cuprates.
Purpose of the Study:
- To investigate the emergence of marginal-Fermi-liquid (MFL) behavior in the Hubbard model on a square lattice.
- To determine the doping dependence of the Fermi surface and single-particle excitations.
- To explore the transition between MFL and Fermi-liquid states.
Main Methods:
- Utilizing a self-consistent projection operator method.
- Calculating the momentum and frequency dependence of single-particle excitations with high resolution.
- Comparing results with finite temperature quantum Monte Carlo simulations.
Main Results:
- Observed MFL-like behavior for a range of hole doping and interaction parameters (U).
- Identified a holelike Fermi surface in the underdoped regime and an electronlike Fermi surface in the overdoped regime.
- Discovered a discontinuous transition from MFL to Fermi-liquid behavior with increasing doping, due to the collapse of the lower Hubbard band.
Conclusions:
- Luttinger's theorem is inapplicable in the underdoped regime due to the observed phase transition.
- The findings provide insights into the complex electronic properties of correlated electron systems.
- The study highlights the importance of the lower Hubbard band collapse in driving electronic phase transitions.
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