Journal Article

Shared control of a 16 semiconductor quantum dot crossbar array

Motz, Sayr, Scappucci, Giordano, Borsoi, Francesco, de Snoo, Sander L., Veldhorst, Menno, John, Valentin, Meyer, Marcel, Sammak, Amir, Hendrickx, Nico W., van Riggelen, Floor

2024

Overview

The efficient control of a large number of qubits is one of the most challenging aspects for practical quantum computing. Current approaches in solid-state quantum technology are based on brute-force methods, where each and every qubit requires at least one unique control line—an approach that will become unsustainable when scaling to the required millions of qubits. Here, inspired by random-access architectures in classical electronics, we introduce the shared control of semiconductor quantum dots to efficiently operate a two-dimensional crossbar array in planar germanium. We tune the entire array, comprising 16 quantum dots, to the few-hole regime. We then confine an odd number of holes in each site to isolate an unpaired spin per dot. Moving forward, we demonstrate on a vertical and a horizontal double quantum dot a method for the selective control of the interdot coupling and achieve a tunnel coupling tunability over more than 10 GHz. The operation of a quantum electronic device with fewer control terminals than tunable experimental parameters represents a compelling step forward in the construction of scalable quantum technology. An efficient control strategy is designed for quantum dot arrays, drawing inspiration from classical semiconductor technology. A two-dimensional array of 16 semiconductor quantum dots is operated using only a few shared control lines.

• Publisher: Nature Publishing Group UK,Nature Publishing Group
• Subject: 639/766/483/2802 / 639/925/927/1007 / Arrays / Chemistry and Materials Science / Coupling / Electrons / Germanium / Materials Science / Nanotechnology / Nanotechnology and Microengineering / Quantum computing / Quantum dots / Qubits (quantum computing) / Random access