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Published on: March 30, 2017
Density-matrix renormalization group study of trapped imbalanced Fermi condensates
1Department of Physics, Tokyo Institute of Technology, 2-12-1 O-okayama, Meguro-ku, Tokyo 152-8551, Japan. tezuka.m.aa@m.titech.ac.jp
Physical Review Letters
|June 4, 2008
Summary
We investigated imbalanced Fermi condensates using the density-matrix renormalization group. Our findings reveal a Fulde-Ferrell-Larkin-Ovchinnikov phase and phase separation in these systems.
Area of Science:
- Condensed Matter Physics
- Quantum Many-Body Systems
Background:
- Understanding the behavior of imbalanced Fermi condensates is crucial for quantum simulation and materials science.
- The one-dimensional attractive Hubbard model provides a simplified yet powerful framework for studying such systems.
Purpose of the Study:
- To investigate the properties of a harmonically trapped imbalanced Fermi condensate using the density-matrix renormalization group.
- To identify the emergence of exotic phases, such as the Fulde-Ferrell-Larkin-Ovchinnikov (FFLO) phase.
Main Methods:
- Utilizing the density-matrix renormalization group (DMRG) algorithm.
- Analyzing the density profiles and two-particle density matrix of the system.
Main Results:
- Observed a flattened population difference between spin-up and spin-down components at the trap center.
- Identified phase separation between the condensate and unpaired majority atoms for specific interaction and imbalance parameters.
- Confirmed the realization of the FFLO phase through periodic sign changes in the order parameter.
- Determined that minority spin atoms contribute to the quasicondensate up to a population imbalance P of approximately 0.8.
Conclusions:
- The study demonstrates the feasibility of realizing the FFLO phase in harmonically trapped imbalanced Fermi condensates.
- Phase separation and the extent of minority spin contribution are sensitive to interaction strength and population imbalance.
- The findings provide testable predictions for future experimental investigations.
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