Magnetic susceptibility of a one-dimensional Fermion-system

H. U. Everts, Wolfram Koch

G. E. Gurgenishvili, A. A. Nersesyan, L. A. Chobanyan

G. I. Japaridze, A. A. Nersesyan

D. Arisa, V. V. França

We investigate the mapping between magnetic susceptibility and entanglement in the metallic, insulating, conventional, and exotic polarized superfluid phases of one-dimensional fermionic lattice systems as described by the Hubbard model. Motivated by recent proposals for determining and quantifying entanglement via magnetic susceptibility measurements, we numerically study the intrinsic relationship between the two quantities at zero temperature. We find signatures of the metal-insulator transition and of the BCS-BEC crossover, but the most relevant result is that for conventional and exotic superfluids the mapping between magnetic susceptibility and entanglement is surprisingly simple: Directly proportional. This linear behavior is found to be universal for conventional superfluids and therefore could be exploited to quantify entanglement in current cold-atom and condensed-matter experiments.

Hugues Nélisse, C. Bourbonnais, Yu. M. Vil’k +2 more

Dai S. Hirashima, Hideaki Takahashi

Wavevector dependence and temperature dependence of magnetic susceptibility of clean interacting fermion systems in two dimensions are investigated by a second order perturbation theory. It is found that the static susceptibility varies linearly with wavevector q in the long wavelength limit at T =0. It is also found that the uniform susceptibility varies linearly with temperature at low temperatures.