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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
From the Cooper problem to canted supersolids in Bose-Fermi mixtures
Peter Anders1, Philipp Werner, Matthias Troyer
1Theoretische Physik, ETH Zurich, 8093 Zurich, Switzerland.
Physical Review Letters
|December 11, 2012
Summary
We mapped the Bose-Fermi Hubbard model phase diagram, revealing superfluid and supersolid phases for fast bosons and charge density waves for slow bosons. These findings are accessible via cold gas experiments.
Area of Science:
- Condensed Matter Physics
- Quantum Simulation
- Ultracold Atomic Gases
Background:
- The Bose-Fermi Hubbard model is crucial for understanding mixtures of bosonic and fermionic atoms.
- Investigating phase diagrams reveals emergent quantum phenomena in interacting many-body systems.
- Dynamical mean-field theory (DMFT) is a powerful tool for studying strongly correlated lattice models.
Purpose of the Study:
- To calculate the phase diagram of the 3D Bose-Fermi Hubbard model at specific filling fractions.
- To explore the influence of boson speed and interspecies interactions on emergent phases.
- To identify phases relevant to current cold gas experimental capabilities.
Main Methods:
- Employed single-site dynamical mean-field theory (DMFT) for calculations.
- Analyzed the Bose-Fermi Hubbard model on a 3D cubic lattice.
- Considered fermionic half filling and bosonic unit filling conditions.
Main Results:
- Identified superfluid and canted supersolid phases driven by interspecies coupling for fast bosons, analogous to the Cooper problem.
- Observed fermionic charge density wave phases favored by slow bosons with attractive interactions.
- Revealed competing instabilities leading to a complex phase diagram.
Conclusions:
- The study elucidates a rich phase diagram for the Bose-Fermi Hubbard model.
- Results highlight the distinct behaviors of fast and slow bosons in interacting mixtures.
- The predicted phases are experimentally accessible with current cold gas technology.
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