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arXiv · 1911.08345

Highly tunable exchange-only singlet-only qubit in a GaAs triple quantum dot

Arnau Sala·Jørgen Holme Qvist·Jeroen Danon
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Abstract

We propose an implementation of a singlet-only spin qubit in a GaAs-based triple quantum dot with a (1,4,1) charge occupation. In the central multi-electron dot, the interplay between Coulomb interaction and an out-of-plane magnetic field creates an energy spectrum with a tunable singlet-triplet splitting, which can be exploited to create a six-particle singlet-only qubit with a qubit splitting that can straightforwardly be tuned over tens of $\mu$eV by adjusting the external magnetic field. We confirm the full exchange-based electric control of the qubit and demonstrate its superior coherence properties due to its singlet-only nature.

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Arnau Sala, Jørgen Holme Qvist, Jeroen Danon. 2019-11-19. Highly tunable exchange-only singlet-only qubit in a GaAs triple quantum dot. https://doi.org/10.1103/physrevresearch.2.012062

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