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Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Time-dependent mean field theory for quench dynamics in correlated electron systems
Marco Schiró1, Michele Fabrizio
1International School for Advanced Studies (SISSA), and CRS Democritos, CNR-INFM, via Bonomea 265, 34136 Trieste Italy.
Physical Review Letters
|September 28, 2010
Summary
A new variational method models quantum dynamics in strongly correlated systems. It reveals a dynamical transition in the fermionic Hubbard model at half-filling, which becomes a crossover with doping.
Area of Science:
- Condensed Matter Physics
- Quantum Dynamics
- Strongly Correlated Electron Systems
Background:
- Understanding quantum dynamics in strongly correlated systems is crucial for materials science.
- Existing methods often face challenges with computational complexity and flexibility.
Purpose of the Study:
- Introduce a flexible variational approach for out-of-equilibrium quantum dynamics.
- Investigate the behavior of the fermionic Hubbard model under a sudden interaction change.
Main Methods:
- Utilize a time-dependent Gutzwiller wave function.
- Apply a variational approach to study quantum dynamics.
- Analyze the fermionic Hubbard model at the mean-field level.
Main Results:
- A rich dynamical behavior was observed in the fermionic Hubbard model.
- A dynamical transition between small and large quantum quench regimes was identified at half-filling.
- This transition was found to change into a crossover at any finite doping.
Conclusions:
- The time-dependent Gutzwiller approach offers a flexible method for studying quantum dynamics.
- The study confirms and extends previous findings on quantum quench dynamics in the Hubbard model.
- The results highlight the distinct behavior at half-filling versus finite doping.
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