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11:21
Cooling an Optically Trapped Ultracold Fermi Gas by Periodical Driving
Published on: March 30, 2017
High-temperature atomic superfluidity in lattice Bose-Fermi mixtures.
Fabrizio Illuminati1, Alexander Albus
1Dipartimento di Fisica, Università di Salerno, INFM--UdR di Salerno, and INFN, Sezione di Napoli--Gruppo Collegato di Salerno, Via S. Allende, I-84081 Baronissi (SA), Italy.
Physical Review Letters
|September 28, 2004
Summary
We explore superfluidity in atomic Bose-Fermi mixtures within optical lattices. Repulsive boson-boson interactions induce attractive fermion pairing, enabling enhanced BEC-BCS crossover and superfluidity, even with direct fermion repulsion.
Area of Science:
- Atomic, Molecular, and Optical Physics
- Quantum Many-Body Physics
- Condensed Matter Theory
Background:
- Bose-Fermi mixtures in optical lattices are crucial for studying quantum phenomena.
- Superfluidity in fermionic systems is typically hindered by repulsive interactions.
- Boson-fermion interactions can mediate novel pairing mechanisms.
Purpose of the Study:
- To investigate the superfluidity of fermionic atoms in Bose-Fermi mixtures.
- To analyze the role of boson-fermion and boson-boson interactions in inducing fermion pairing.
- To explore the BEC-BCS crossover in such systems.
Main Methods:
- Theoretical analysis of atomic Bose-Fermi mixtures in optical lattices.
- Derivation of effective fermion-fermion interactions from boson-fermion coupling.
- Investigation of s-wave pairing and superfluid properties.
Main Results:
- Boson-boson repulsive on-site interactions always induce attractive fermion-fermion coupling.
- An enhanced BEC-BCS crossover is predicted as lattice potential strength is varied.
- Induced attraction enables s-wave superfluidity even with direct on-site fermion repulsion.
Conclusions:
- Boson-fermion interactions provide a viable route to induce superfluidity in fermionic systems.
- The findings offer a new perspective on controlling quantum phases in ultracold atomic gases.
- This work highlights the potential for novel quantum states in engineered Bose-Fermi mixtures.
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