Hole Dynamics in an Antiferromagnet

The interplay of spin and charge degrees of freedom in a doped anti-ferromagnet is a fundamental ingredient that gives rise to the exotic physical behavior observed in these systems. This includes non-Fermi liquid transport properties, the pseudogap features in ARPES spectra, ...

We study this problem on the most fundamental level, in a time- and space- resolved way in a clean 2D Hubbard / t-J model. In a recent collaboration with Harvard's Greiner lab we observed the dynamical formation of a magnetic polaron, after releasing an initially pinned hole inside an extended anti-ferromagnet.

In agreement with our earlier theoretical simulations (including TUM/MPQ collaborations) we find a two-stage dynamical process: A fast initial spreading followed by a slow expansion which depends on the strength of the spin-exchange coupling. The collection of theoretical and experimental observation can be largely explained - even quantitatively - by a microscopic spinon-chargon description of the dynamically evolving magnetic polaron.