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arXiv · 2308.00839

Superconducting qubit based on twisted cuprate van der Waals heterostructures

Valentina Brosco·Giuseppe Serpico·Valerii Vinokur·Nicola Poccia·Uri Vool
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Abstract

Van-der-Waals (vdW) assembly enables the fabrication of novel Josephson junctions utilizing an atomically sharp interface between two exfoliated and relatively twisted $\rm{Bi_2Sr_2CaCu_2O_{8+x}}$ (Bi2212) flakes. In a range of twist angles around $45^\circ$, the junction provides a regime where the interlayer two-Cooper pair tunneling dominates the current-phase relation. Here we propose to employ this novel junction to realize a capacitively shunted qubit that we call flowermon. The $d$-wave nature of the order parameter endows the flowermon with inherent protection against charge-noise-induced relaxation and quasiparticle-induced dissipation. This inherently protected qubit paves the way to a new class of high-coherence hybrid superconducting quantum devices based on unconventional superconductors.

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Valentina Brosco, Giuseppe Serpico, Valerii Vinokur, Nicola Poccia, Uri Vool. 2023-08-01. Superconducting qubit based on twisted cuprate van der Waals heterostructures. https://arxiv.org/abs/2308.00839

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