Low-entropy arrays of microwave-shielded molecules prepared by interaction blockade

TL;DR

This paper proposes a robust method for preparing large arrays of microwave-shielded ultracold molecules in the motional ground state with high fidelity, enabling scalable quantum technologies.

Contribution

It introduces a deterministic loading scheme using interaction blockade to achieve low-entropy, ground-state molecular arrays in optical traps.

Findings

Fidelity exceeding 99% for small trap volumes

Scalable to thousands of traps limited by reservoir molecules

Prevents multiparticle occupancy through strong repulsion

Abstract

Ultracold molecules are becoming an increasingly important technology for quantum simulation, computation, and sensing, but their state preparation in large, low-entropy arrays remains a key challenge. We propose to deterministically load single molecules into optical tweezer arrays or lattices from either thermal or degenerate gases, with a high probability of occupying the tweezer's motional ground state. Strong repulsion between microwave-shielded molecules prevents multiparticle occupancy. Our proposal represents a robust scheme for deterministic single molecule preparation directly in the motional ground state with expected fidelities exceeding 99 percent for small trap volumes and highly polar species. This method can be scaled to thousands of traps limited by the reservoir molecule number, opening the door to large, low-entropy polar molecule arrays for quantum computation, quantum simulation, and precision measurement.