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arXiv · 1612.07292

Superconducting grid-bus surface code architecture for hole-spin qubits

Simon E. Nigg·Andreas Fuhrer·Daniel Loss
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Abstract

We present a scalable hybrid architecture for the 2D surface code combining superconducting resonators and hole-spin qubits in nanowires with tunable direct Rashba spin-orbit coupling. The back-bone of this architecture is a square lattice of capacitively coupled coplanar waveguide resonators each of which hosts a nanowire hole-spin qubit. Both the frequency of the qubits and their coupling to the microwave field are tunable by a static electric field applied via the resonator center pin. In the dispersive regime, an entangling two-qubit gate can be realized via a third order process, whereby a virtual photon in one resonator is created by a first qubit, coherently transferred to a neighboring resonator, and absorbed by a second qubit in that resonator. Numerical simulations with state-of-the-art coherence times yield gate fidelities approaching the $99\%$ fault tolerance threshold.

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Simon E. Nigg, Andreas Fuhrer, Daniel Loss. 2016-12-21. Superconducting grid-bus surface code architecture for hole-spin qubits. https://doi.org/10.1103/physrevlett.118.147701

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