Quantum magnetism and topological ordering via enhanced Rydberg-dressing near F\"orster-resonances

TL;DR

This paper proposes a cold-atom method using enhanced Rydberg-dressing near F"orster-resonances to realize controllable quantum magnetic interactions and topological phases, enabling exploration of quantum magnetism with tunable parameters.

Contribution

It introduces a novel Rydberg-dressing scheme exploiting F"orster-resonances to achieve large, controllable spin interactions for quantum magnetism and topological phases in cold-atom systems.

Findings

Enhanced Rydberg-dressing yields strong spin interactions exceeding decoherence rates.

Demonstration of dynamical preparation of topological magnetic phases.

Viable route for exploring quantum magnetism with tunable interactions in cold atoms.

Abstract

We devise a cold-atom approach to realizing a broad range of bi-linear quantum magnets. Our scheme is based on off-resonant single-photon excitation of Rydberg $P$-states (Rydberg-dressing), whose strong interactions are shown to yield controllable XYZ-interactions between effective spins, represented by different atomic ground states. The distinctive features of F\"orster-resonant Rydberg atom interactions are exploited to enhance the effectiveness of Rydberg-dressing and, thereby, yield large spin-interactions that greatly exceed corresponding decoherence rates. We illustrate the concept on a spin-1 chain implemented with cold Rubidium atoms, and demonstrate that this permits the dynamical preparation of topological magnetic phases. Generally, the described approach provides a viable route to exploring quantum magnetism with dynamically tuneable (an)isotropic interactions as well as variable space- and spin-dimensions in cold-atom experiments.