3 research outputs found
Anisotropy-mediated reentrant localization
We consider a 2d dipolar system, , with the generalized dipole-dipole
interaction , with the power controlled experimentally in
trapped-ion or Rydberg-atom systems via their interaction with cavity modes. We
focus on the dilute dipolar excitation case when the problem can be effectively
considered as single-particle with the interaction providing long-range
dipolar-like hopping. % We show that the spatially homogeneous tilt of
the dipoles giving rise to the anisotropic dipole exchange leads to the
non-trivial reentrant localization beyond the locator expansion, , unlike
the models with random dipole orientation. The Anderson transitions are found
to occur at the finite values of the tilt parameter , , and
, , showing the robustness of the localization at
small and large anisotropy values. % Both extensive numerical calculations and
analytical methods show power-law localized eigenstates in the bulk of the
spectrum, obeying recently discovered duality of their
spatial decay rate, on the localized side of the transition, . This
localization emerges due to the presence of the ergodic extended states at
either spectral edge, which constitute a zero fraction of states in the
thermodynamic limit, decaying though extremely slowly with the system size.Comment: 11 pages, 5 figures, 80 references (in 6 pages) + 14 pages, 11
figures in Appendice