Modeling strongly correlated electron systems using cold atoms
Eugene Demler
Physics Department
Harvard University
Bose-Einstein condensation
Scattering length is much smaller than characteristic interparticle distances. Interactions are weak
New Era in Cold Atoms Research
Focus on Systems with Strong Interactions
• Optical lattices
• Feshbach resonances
• Low dimensional systems
Why are we interested in quantum systems with strong interactions?
Strongly correlated electron systems in novel quantum materials
Transition metals and their oxides (including cuprates, manganites), actinides, lanthanides, heavy fermion compounds, organic materials, …
Unusual properties of materials withstrong electron correlations
High temperature superconductivity
Quantum magnetism
Electron fractionalization
?
= +electron charge spin
Applications of quantum materials: Ferroelectric RAM
Non-Volatile Memory
High Speed Processing
FeRAM in Smart Cards
V+ + + + + + + +
_ _ _ _ _ _ _ _
Modeling quantum systems
R. Feynman (1982)
Analogue quantum computer. Simulation of one quantum system by another.
Tc 93 K
t
U
t
Fermionic atoms in optical lattices
Strongly correlated systemsAtoms in optical latticesElectrons in Solids
Simple metalsPerturbation theory in Coulomb interaction applies. Band structure methods wotk
Strongly Correlated Electron SystemsBand structure methods fail.
Novel phenomena in strongly correlated electron systems:
Quantum magnetism, phase separation, unconventional superconductivity,high temperature superconductivity, fractionalization of electrons …
Can we understand high Tc cuprates using the fermionic Hubbard model?
t
U
t
Antiferomagnetic order
Do we have d-wave pairing?
-
Vortices in fermionic superfluids
Experiments with fermionic superfluids of cold atoms will help us understand important basic properties of vortices
Vortices in ultracold fermionic atomsVortices in high-Tc cuprates
Pairing in systems with imbalanced spin population
Possible FFLO phase in CeCoIn5
Pairing in polarized Fermi gas
New Era in Cold Atoms ResearchFocus on Systems with Strong Interactions
Goals
• Resolve long standing questions in condensed matter physics (e.g. origin of high temperature superconductivity)
• Resolve matter of principle questions (e.g. existence of FFLO phase)
• Study new phenomena in strongly correlated systems (e.g. coherent far from equilibrium dynamics)
Top Related