Competing delocalisation and localisation induced by the dipolar tail in fragmented lattice gases
Abstract
We investigate how the long-range tail of dipole-dipole interactions modifies the dynamics of strongly interacting hard-core bosons in a one-dimensional lattice. In the nearest-neighbour model, large interactions generate an emergent Hilbert-space fragmentation into manifolds labelled by the number of nearest-neighbour bonds NNN. The dipolar tail has a non-monotonic effect on this fragmented dynamics as the interaction-to-tunnelling ratio V/t is increased. At intermediate V/t, it enhances delocalisation relative to the nearest-neighbour model by reducing the energetic detuning between neighbouring NNN manifolds and sustaining their hybridisation by hopping. At larger V/t, the same tail lifts degeneracies within each manifold, beginning with the splitting associated with the next-nearest-neighbour bond number NNNN, and promotes intra-manifold localisation and Hilbert-space shattering. The competition between these two effects produces a crossover from a delocalising to a localising role of the dipolar tail, visible in the late-time spatial inhomogeneity. This crossover occurs for nearly all initial states considered and persists at different fillings. Transverse confinement strengthens the short-range part of the dipolar tail and shifts the crossover to lower V/t, bringing it into the regime relevant to current experiments with magnetic atoms and polar molecules.
Related
- Non-adiabatic Optimisation via Localisation-Delocalisation Transitions
- Weak-Flow Induced Dielectric Axes Rotation in Dipolar Suspensions
- Competing lattice structures induced by Sn substitution in CsV3Sb5
- Chirality-induced spin selectivity as a nonequilibrium effect: a unified test of competing mechanisms
- Delocalisation and scaling limit for the disordered long-range Discrete Gaussian Chain
BibTeX
@misc{gupta2026competing,
title = {{Competing delocalisation and localisation induced by the dipolar tail in fragmented lattice gases}},
author = {Sabhyata Gupta and Adith Sai Aramthottil and Luis Santos},
howpublished = {arXiv},
year = {2026},
month = oct,
doi = {10.48550/arxiv.2610.18747},
eprint = {2610.18747},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2610.18747},
note = {CC BY 4.0},
}
RIS
TY - UNPB
TI - Competing delocalisation and localisation induced by the dipolar tail in fragmented lattice gases
AU - Sabhyata Gupta
AU - Adith Sai Aramthottil
AU - Luis Santos
PY - 2026
DA - 2026/10/13
PB - arXiv
DO - 10.48550/arxiv.2610.18747
UR - https://arxiv.org/abs/2610.18747
AB - We investigate how the long-range tail of dipole-dipole interactions modifies the dynamics of strongly interacting hard-core bosons in a one-dimensional lattice. In the nearest-neighbour model, large interactions generate an emergent Hilbert-space fragmentation into manifolds labelled by the number of nearest-neighbour bonds N_NN. The dipolar tail has a non-monotonic effect on this fragmented dynamics as the interaction-to-tunnelling ratio V/t is increased. At intermediate V/t, it enhances delocalisation relative to the nearest-neighbour model by reducing the energetic detuning between neighbouring N_NN manifolds and sustaining their hybridisation by hopping. At larger V/t, the same tail lifts degeneracies within each manifold, beginning with the splitting associated with the next-nearest-neighbour bond number N_NNN, and promotes intra-manifold localisation and Hilbert-space shattering. The competition between these two effects produces a crossover from a delocalising to a localising role of the dipolar tail, visible in the late-time spatial inhomogeneity. This crossover occurs for nearly all initial states considered and persists at different fillings. Transverse confinement strengthens the short-range part of the dipolar tail and shifts the crossover to lower V/t, bringing it into the regime relevant to current experiments with magnetic atoms and polar molecules.
ER -