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

Abstract

Quantum walks provide a framework for 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. We do this by combining the fast, programmable control provided by optical tweezers with the scalable, homogeneous environment of an optical lattice. With these tools we study continuous-time quantum walks of single atoms on a square lattice and perform proof-of-principle demonstrations of spatial search with these walks. When scaled to more particles, the capabilities demonstrated can be extended to study a variety of problems in quantum information science, including performing more effective versions of spatial search using a larger graph with increased connectivity. Description Combining lattices and tweezers Optical lattices have been used as a platform for quantum simulation for the past two decades. More recently, arrays of optical tweezers, which have the advantage of rapid reconfigurability, have risen to prominence. Young et al. combined these tools to perform large-scale quantum walks of strontium-88 atoms prepared in optical tweezers and then implanted into the sites of an optical lattice. The combined platform holds promise for applications in quantum science. —JS A spatial search was performed using quantum walks of strontium-88 atoms in a combined optical tweezer-lattice platform.