A coherence sweet spot with enhanced dipolar coupling

• URL: http://arxiv.org/abs/2405.10796v2
• Date: Thu, 30 May 2024 03:09:04 GMT
• Title: A coherence sweet spot with enhanced dipolar coupling
• Authors: Jann H. Ungerer, Alessia Pally, Stefano Bosco, Artem Kononov, Deepankar Sarmah, Sebastian Lehmann, Claes Thelander, Ville F. Maisi, Pasquale Scarlino, Daniel Loss, Andreas Baumgartner, Christian Schönenberger,
• Abstract summary: We demonstrate a compromise-free singlet-triplet (ST) qubit, where the qubit couples maximally to the driving field. We demonstrate a spin qubit sweet spot maximizing the dipolar coupling and simultaneously minimizing the decoherence. These findings pave the way for enhanced engineering of these nanomaterials for next-generation qubit technologies.
• Score: 0.0
• License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
• Abstract: Qubits require a compromise between operation speed and coherence. Here, we demonstrate a compromise-free singlet-triplet (ST) qubit, where the qubit couples maximally to the driving field while simultaneously coupling minimally to the dominant noise sources. The qubit is implemented in a crystal-phase defined double-quantum dot in an InAs nanowire. Using a superconducting resonator, we measure the spin-orbit interaction (SOI) gap, the spin-photon coupling strength and the qubit decoherence rate as a function of the in-plane magnetic-field orientation. We demonstrate a spin qubit sweet spot maximizing the dipolar coupling and simultaneously minimizing the decoherence. Our theoretical description postulates phonons as the most likely dominant noise source. The compromise-free sweet spot originates from the SOI suggesting that it is not restricted to this material platform, but might find applications in any material with SOI. These findings pave the way for enhanced engineering of these nanomaterials for next-generation qubit technologies.

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