Few-qubit quantum-classical simulation of strongly correlated lattice fermions

  1. Juha M Kreula,
  2. Laura García-Álvarez,
  3. Lucas Lamata,
  4. Stephen R Clark,
  5. Enrique Solano,
  6. and Dieter Jaksch
We study a proof-of-principle example of the recently proposed hybrid quantum-classical simulation of strongly correlated fermion models in the thermodynamic limit. In a „two-site“
dynamical mean-field theory (DMFT) approach we reduce the Hubbard model to an effective impurity model subject to self-consistency conditions. The resulting minimal two-site representation of the non-linear hybrid setup involves four qubits implementing the impurity problem, plus an ancilla qubit on which all measurements are performed. We outline a possible implementation with superconducting circuits feasible with near-future technology.