Interacting Quantum Spin Chains with Molecular Tweezer Arrays: From Out-of-Equilibrium Quantum Dynamics to Spin-Squeezing

Programmable molecular tweezer arrays are an emerging platform for quantum science and precision measurement. In the past few years, our group and others have significantly advanced the level of quantum control over this platform. Crucially, the building blocks for quantum science, such as high-fidelity preparation and detection and deterministic entanglement, have now been demonstrated. These developments open the door for practical applications in simulation of quantum many-body systems, quantum information processing, and quantum-enhanced sensing.

In this talk, I will report our recent work where we have performed the first quantum many-body simulation experiments and spin-squeezing experiments in molecular arrays. Using two new capabilities that we have developed - mid-circuit enhanced quantum state preparation and Floquet Hamiltonian engineering of effective spin-spin interactions, we have realized quantum spin models with tunable 1/r^3 XX/XXZ/XYZ interactions in 1D chains. I will first report on the out-of-equilibrium quantum dynamics that we have observed in these spin chains, which include quantum walks of single spin excitations, dynamics of repulsive magnon bound states, and coherent pair creation. I will then discuss how these spin models can be used to create long-lived spin-squeezed states, which are metrologically useful entangled states that provide suppressed quantum projection noise. If time permits, I will report on the first demonstration of spin-squeezing of molecules.