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arXiv · 2002.02312

Controlling magnetic correlations in a driven Hubbard system far from half-filling

Hongmin Gao·Jonathan R. Coulthard·Dieter Jaksch·Jordi Mur-Petit
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Abstract

We propose using ultracold fermionic atoms trapped in a periodically shaken optical lattice as a quantum simulator of the t-J Hamiltonian, which describes the dynamics in doped antiferromagnets and is thought to be relevant to the problem of high-temperature superconductivity in the cuprates. We show analytically that the effective Hamiltonian describing this system for off-resonant driving is the t-J model with additional pair hopping terms, whose parameters can all be controlled by the drive. We then demonstrate numerically using tensor network methods for a 1D lattice that a slow modification of the driving strength allows near-adiabatic transfer of the system from the ground state of the underlying Hubbard model to the ground state of the effective t-J Hamiltonian. Finally, we report exact diagonalization calculations illustrating the control achievable on the dynamics of spin-singlet pairs in 2D lattices utilising this technique with current cold-atom quantum-simulation technology. These results open new routes to explore the interplay between density and spin in strongly-correlated fermionic systems through their out-of-equilibrium dynamics.

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Hongmin Gao, Jonathan R. Coulthard, Dieter Jaksch, Jordi Mur-Petit. 2020-02-06. Controlling magnetic correlations in a driven Hubbard system far from half-filling. https://doi.org/10.1103/physreva.101.053634

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