Highly tunable 2D silicon quantum dot array with coupling beyond nearest neighbors

TL;DR

This paper demonstrates a highly tunable 2D silicon quantum dot array with controllable couplings beyond nearest neighbors, advancing scalable quantum computing platforms.

Contribution

It introduces a controllable 2D silicon quantum dot array with tunable nearest and next-nearest neighbor couplings, enabling flexible quantum device configurations.

Findings

Independent control over electron fillings and tunnel couplings.

Wide tuning of next-nearest-neighbor tunnel couplings.

Array configuration can be altered as needed.

Abstract

Scaling up quantum dots to two-dimensional (2D) arrays is a crucial step for advancing semiconductor quantum computation. However, maintaining excellent tunability of quantum dot parameters, including both nearest-neighbor and next-nearest-neighbor couplings, during 2D scaling is challenging, particularly for silicon quantum dots due to their relatively small size. Here, we present a highly controllable and interconnected 2D quantum dot array in planar silicon, demonstrating independent control over electron fillings and the tunnel couplings of nearest-neighbor dots. More importantly, we also demonstrate the wide tuning of tunnel couplings between next-nearest-neighbor dots,which plays a crucial role in 2D quantum dot arrays. This excellent tunability enables us to alter the coupling configuration of the array as needed. These results open up the possibility of utilizing silicon quantum dot arrays as versatile platforms for quantum computing and quantum simulation.