Applied Physics Letters

Individual two-axis control of three singlet-triplet qubits in a micromagnet integrated quantum dot array

Wonjin Jang, Min-Kyun Cho, Jehyun Kim, Hwanchul Chung, V. Umansky, Dohun Kim

Published Dec 7, 2020• 11 citations

Abstract

The individual confinement and two-axis qubit operations of two-electron spin qubits in a GaAs gate-defined sextuple quantum dot array with an integrated micromagnet are reported in this study. As a first step toward multiple-qubit operations, we demonstrate coherent manipulations of three singlet-triplet qubits showing underdamped Larmor and Ramsey oscillations in all double dot sites. An accurate measurement of site-dependent field gradients as well as root-mean-squared electric and magnetic noise is provided, which is followed by a discussion of the adequacy of a simple rectangular micromagnet for practical use in multiple quantum dot arrays. Current limitations and possible strategies for achieving simultaneous multi-qubit operations in extended linear arrays are also presented.

DOI: 10.1063/5.0031231

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