Two-axis twisting using Floquet-engineered XYZ spin models with polar molecules

TL;DR

This paper demonstrates Floquet engineering of polar molecules in optical lattices to realize complex spin models, including two-axis twisting dynamics, enabling advanced quantum simulations and entangled state generation.

Contribution

It introduces a method to engineer XYZ spin models with polar molecules using Floquet techniques, expanding the possibilities for quantum simulation beyond static field limitations.

Findings

Validated XXZ spin models via Floquet microwave pulses and dc electric fields.

Observed two-axis twisting mean-field dynamics in 2D molecular layers.

Showed potential for generating entangled states for quantum measurement.

Abstract

Polar molecules confined in an optical lattice are a versatile platform to explore spin-motion dynamics based on strong, long-range dipolar interactions. The precise tunability of Ising and spin-exchange interactions with both microwave and dc electric fields makes the molecular system particularly suitable for engineering complex many-body dynamics. Here, we used Floquet engineering to realize interesting quantum many-body systems of polar molecules. Using a spin encoded in the two lowest rotational states of ultracold KRb molecules, we mutually validated XXZ spin models tuned by a Floquet microwave pulse sequence against those tuned by a dc electric field through observations of Ramsey contrast dynamics, setting the stage for the realization of Hamiltonians inaccessible with static fields. In particular, we observed two-axis twisting mean-field dynamics, generated by a Floquet-engineered XYZ model using itinerant molecules in 2D layers. In the future, Floquet-engineered Hamiltonians could generate entangled states for molecule-based precision measurement or could take advantage of the rich molecular structure for quantum simulation of multi-level systems.