arXiv:1305.2526 · Annalen der Physik

Quantum simulations of localization effects with dipolar interactions

Gonzalo A. Álvarez, Robin Kaiser, Dieter Suter

Published Oct 8, 2013• 22 citations

Abstract

Quantum information processing often uses systems with dipolar interactions. Here a nuclear spin‐based quantum simulator is used to study the spreading of information in such a dipolar‐coupled system. While the information spreads with no apparent limits in the case of ideal dipolar couplings, additional perturbations limit the spreading, leading to localization. In previous work [Phys. Rev. Lett. 104, 230403 (2010)], it was found that the system size reaches a dynamic equilibrium that decreases with the square of the perturbation strength. This work examines the impact of a disordered Hamiltonian with dipolar interactions. It shows that the expansion of the cluster of spins freezes in the presence of large disorder, reminiscent of Anderson localization of non‐interacting waves in a disordered potential.

DOI: 10.1002/andp.201300096

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