Tweezer-programmable 2D quantum walks in a Hubbard-regime lattice

TL;DR

This paper introduces a new method combining optical tweezer arrays with optical lattices to control 2D quantum walks, enabling programmable, coherent manipulation for quantum algorithms and simulations.

Contribution

It demonstrates the first integration of optical tweezer control with optical lattices for programmable 2D quantum walks, including proof-of-principle spatial search demonstrations.

Findings

Successful implementation of continuous-time quantum walks on a 2D lattice

Proof-of-principle spatial search using quantum walks

Potential for scalable quantum simulation and information processing

Abstract

Quantum walks provide a framework for understanding and designing quantum algorithms that is both intuitive and universal. To leverage the computational power of these walks, it is important to be able to programmably modify the graph a walker traverses while maintaining coherence. Here, we do this by combining the fast, programmable control provided by optical tweezer arrays with the scalable, homogeneous environment of an optical lattice. Using this new combination of tools we study continuous-time quantum walks of single atoms on a 2D square lattice, and perform proof-of-principle demonstrations of spatial search using these walks. When scaled to more particles, the capabilities demonstrated here can be extended to study a variety of problems in quantum information science and quantum simulation, including the deterministic assembly of ground and excited states in Hubbard models with tunable interactions, and performing versions of spatial search in a larger graph with increased connectivity, where search by quantum walk can be more effective.