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Fully polarized Fermi systems at finite temperature
Krzysztof Myśliwy1, Marek Napiórkowski1
1Institute of Theoretical Physics, Faculty of Physics, <a href="https://ror.org/039bjqg32">University of Warsaw</a>, Pasteura 5, 02-093 Warsaw, Poland.
Physical Review. E
|October 19, 2024
Summary
We modeled interacting Fermi gases in 2D and 3D, revealing distinct phase diagrams. These differences, driven by the Pauli exclusion principle, depart from standard theories.
Area of Science:
- Condensed matter physics
- Statistical mechanics
- Quantum many-body systems
Background:
- Understanding the thermodynamic behavior of interacting quantum gases is crucial.
- Fermi gases exhibit unique properties due to the Pauli exclusion principle.
Purpose of the Study:
- To develop a model for interacting, fully spin-polarized Fermi gases in 2 and 3 dimensions.
- To investigate the thermodynamic properties and phase transitions of these systems.
Main Methods:
- Derivation of approximate energy spectrum and Helmholtz free energy formulas.
- Analysis of thermodynamic behavior and identification of phase transition lines.
- Comparison of phase diagrams in 2D and 3D.
Main Results:
- Approximate expressions for energy spectrum and free energy derived.
- Lines of first-order phase transitions identified, terminating at critical points.
- Qualitatively different phase diagrams for 2D and 3D Fermi gases observed.
- Phase diagram properties show sensitive dependence on interparticle attraction.
Conclusions:
- The fermionic nature and Pauli exclusion principle lead to unique phase diagrams.
- The model departs from standard van der Waals theory due to quantum effects.
- Dimensionality significantly impacts the thermodynamic and phase behavior of Fermi gases.
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