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arXiv · 2009.13182

Three individual two-axis control of singlet-triplet qubits in a micromagnet integrated quantum dot array

Wonjin Jang·Min-Kyun Cho·Jehyun Kim·Hwanchul Chung·Vladimir Umansky·Dohun Kim
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Abstract

We report individual confinement and two-axis qubit operations of two electron spin qubits in GaAs gate-defined sextuple quantum dot array with integrated micro-magnet. 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. We provide an accurate measure of site site-dependent field gradients and rms electric and magnetic noise, and we discuss the adequacy of simple rectangular micro-magnet for practical use in multiple quantum dot arrays. We also discuss current limitations and possible strategies for realizing simultaneous multi multi-qubit operations in extended linear arrays.

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Wonjin Jang, Min-Kyun Cho, Jehyun Kim, Hwanchul Chung, Vladimir Umansky, Dohun Kim. 2020-10-02. Three individual two-axis control of singlet-triplet qubits in a micromagnet integrated quantum dot array. https://doi.org/10.1063/5.0041232

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