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Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
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Complete spectrum of the infinite-U Hubbard ring using group theory
Alessandro Soncini1, Willem Van den Heuvel1
1School of Chemistry, The University of Melbourne, VIC 3010, Australia.
The Journal of Chemical Physics
|May 17, 2014
Summary
This study provides the first analytical solution for the degeneracy of the N-Hubbard ring model with N-1 electrons. It uses combinatorial and group theory methods to solve strongly correlated mixed-valence problems.
Area of Science:
- Quantum Chemistry
- Condensed Matter Physics
- Mathematical Physics
Background:
- The N-Hubbard model describes strongly correlated electrons in materials.
- Mixed-valence systems exhibit complex electronic behaviors.
- Analytical solutions for degeneracy in such systems are challenging.
Purpose of the Study:
- To provide a full analytical solution for the degeneracy of the N-Hubbard ring model with N-1 electrons and infinite on-site repulsion.
- To present the analytical determination of degeneracy for the first time.
- To develop a general strategy applicable to arbitrary electron counts.
Main Methods:
- Mapping the Hubbard model to Hückel-annulene problems.
- Solving combinatorial enumeration problems (necklace problem) for N-1 beads and two colors.
- Applying the subduction of coset representation technique from group theory.
Main Results:
- A complete analytical solution for the Hubbard model, including degeneracy count, is achieved.
- The number and size of effective Hückel annulenes are determined.
- A general group theoretical strategy is established for solving the one-hole infinite-U Hubbard problem.
Conclusions:
- The study offers a novel and elegant group theoretical strategy for solving the infinite-U Hubbard model.
- The method provides a general approach for analyzing systems with arbitrary electron counts.
- This work advances the understanding of strongly correlated electron systems and their degeneracies.
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