A Flexible Design Platform for Si/SiGe Exchange-Only Qubits with Low Disorder

• DOI: 10.1021/acs.nanolett.1c03026
• Publication Date: 2021-11-22T13:44:08Z
• Authors: Wonill Ha; Sieu D. Ha; Maxwell D. Choi; Yan Tang; Adele E. Schmitz; Mark P. Levendorf; Kangmu Lee; James M. Chappell; Tower S. Adams; Daniel R. Hulbert; Edwin Acuna; Ramsey S. Noah; Justine W. Matten; Michael P. Jura; Jeffrey A. Wright; Matthew T. Rakher; Matthew G. Borselli
• Keywords: Quantum Physics; 0303 health sciences; 03 medical and health sciences; Condensed Matter - Mesoscale and Nanoscale Physics; Mesoscale and Nanoscale Physics (cond-mat.mes-hall); FOS: Physical sciences; Quantum Physics (quant-ph)

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.