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Updated: Jul 11, 2026
11:03
An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Efficient dynamical mean field simulation of the Holstein-Hubbard model.
Philipp Werner1, Andrew J Millis
1Columbia University, New York, NY 10027, USA.
Physical Review Letters
|October 13, 2007
Summary
We developed an efficient, exact method for impurity models with electron-phonon coupling. This approach allows studying the Holstein-Hubbard model under strong interactions and low temperatures, revealing limitations of current theories.
Area of Science:
- Condensed Matter Physics
- Quantum Many-Body Theory
Background:
- Electron-phonon coupling is crucial for understanding material properties.
- Existing methods often involve approximations or are computationally expensive.
Purpose of the Study:
- To present a novel, efficient, and exact method for solving impurity models with electron-phonon coupling.
- To investigate the Holstein-Hubbard model at strong interactions and low temperatures.
Main Methods:
- An efficient, approximation-free treatment of phonons.
- Application to the Holstein-Hubbard model within the dynamical mean-field approximation.
Main Results:
- The method enables access to regimes of strong interactions, very low temperatures, and arbitrary fillings.
- Renormalized Migdal-Eliashberg theory is validated for strongly doped systems.
- The limits of Migdal-Eliashberg theory were identified when quasiparticle energy approaches phonon frequency.
Conclusions:
- The new method provides accurate insights into electron-phonon interactions in complex models.
- It highlights the breakdown of certain theoretical approximations under specific conditions.
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