A flexible design platform for Si/SiGe exchange-only qubits with low disorder

TL;DR

This paper introduces SLEDGE, a versatile silicon qubit platform combining CMOS-like wafer processing with direct-write lithography, achieving low disorder and demonstrating coherent qubit control.

Contribution

The paper presents a novel Si qubit device platform that enables flexible layouts and reduced disorder, advancing scalable silicon quantum computing technology.

Findings

Reduced electrostatic disorder compared to traditional devices

Demonstration of spin coherent exchange oscillations

Single qubit randomized benchmarking results

Abstract

Spin-based silicon quantum dots are an attractive qubit technology for quantum information processing with respect to coherence time, control, and engineering. Here we present an exchange-only Si qubit device platform that combines the throughput of CMOS-like wafer processing with the versatility of direct-write lithography. The technology, which we coin "SLEDGE," features dot-shaped gates that are patterned simultaneously on one topographical plane and subsequently connected by vias to interconnect metal lines. The process design enables non-trivial layouts as well as flexibility in gate dimensions, material selection, and additional device features such as for rf qubit control. We show that the SLEDGE process has reduced electrostatic disorder with respect to traditional overlapping gate devices with lift-off metallization, and we present spin coherent exchange oscillations and single qubit blind randomized benchmarking data.