Evidence of attraction between charge carriers in a doped Mott insulator

Recent progress in optically trapped ultracold atomic gases is now making it possible to access microscopic observables in doped Mott insulators, which are the parent states of high-temperature superconductors. This makes it possible to address longstanding questions about the temperature scales at which attraction between charge carriers are present, and their mechanism. Controllable theoretical results for this problem are not available at low temperature due to the sign problem. In this work, we make important progress with this problem by employing worm-algorithm Monte Carlo, which allows us to obtain completely unbiased results for two charge carriers in a Mott insulator. Our method gives access to lower temperatures than what is currently possible in experiments, and provides evidence for attraction between dopants at a temperature scale that is now feasible in ultracold atomic systems. We also report on spin correlations in the presence of charge carriers, which are directly comparable to experiments.

Automated summary

Recent advances in optically trapped ultracold atomic gases have enabled access to microscopic observables in doped Mott insulators, addressing questions about attraction between charge carriers and their mechanisms. By employing the worm-algorithm Monte Carlo method, unbiased results for two charge carriers in a Mott insulator have been obtained, allowing access to lower temperatures than current experiments and providing evidence for attraction between dopants at feasible temperature scales in ultracold atomic systems.