Modeling strongly correlated electron systems using cold atoms

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Modeling strongly correlated electron systems
using cold atoms

• Eugene Demler
• Physics Department
• Harvard University

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Bose-Einstein condensation
Scattering length is much smaller than
characteristic interparticle distances.
Interactions
are weak
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New Era in Cold Atoms Research
Focus on Systems with Strong Interactions

• Feshbach resonances

• Optical lattices

• Low dimensional systems

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Strongly correlated electron systems in novel
quantum materials
Why are we interested in quantum systems with
strong interactions?
Transition metals and their oxides (including
cuprates, manganites), actinides, lanthanides,
heavy fermion compounds, organic materials,
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Unusual properties of materials withstrong
electron correlations
High temperature superconductivity
Quantum magnetism


Electron fractionalization
spin
electron
charge
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Applications of quantum materialsHigh Tc
superconductors
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Applications of quantum materials Ferroelectric
RAM
V

_ _ _ _ _ _ _ _

FeRAM in Smart Cards
Non-Volatile Memory
High Speed Processing
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Modeling in physics
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Modeling quantum systems
Fermionic atoms in optical lattices
Tc 93 K
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Strongly correlated systems
Simple metals
Perturbation theory in Coulomb interaction
applies. Band structure methods wotk
Strongly Correlated Electron Systems
Band structure methods fail.
Novel phenomena in strongly correlated electron
systems
Quantum magnetism, phase separation,
unconventional superconductivity, high
temperature superconductivity, fractionalization
of electrons
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Examples of questions that can be addressed in
experiments with cold atoms
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Can we understand high Tc cuprates using the
fermionic Hubbard model?
Antiferomagnetic order
Do we have d-wave pairing?
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Vortices in fermionic superfluids
Vortices in ultracold fermionic atoms
Vortices in high-Tc cuprates
Experiments with fermionic superfluids of cold
atoms will help us understand important basic
properties of vortices
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Pairing in systems with imbalanced spin
population
Pairing in polarized Fermi gas
Possible FFLO phase in CeCoIn5
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New Era in Cold Atoms Research
Focus 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)