Quantum computations and simulations require strong coherent coupling between qubits, which may be spatially separated. Achieving this coupling for solid-state-based spin qubits is a long-standing challenge. Here we theoretically investigate a method for achieving such a coupling, based on superconducting nanostructures designed to channel the magnetic flux created by the qubits. We detail semiclassical analytical calculations and simulations of the magnetic field created by a magnetic dipole, depicting the spin qubit, positioned directly below nanofabricated apertures in a superconducting layer. We show that such structures could channel the magnetic flux, enhancing the dipole-dipole interaction between spin qubits and changing its scaling with distance, thus potentially paving the way for controllably engineering an interacting spin system.
Bibliographical noteFunding Information:
This work was originally motivated by discussions with Amir Yacoby. N.B. acknowledges support from the European Union's Horizon 2020 research and innovation program under grant agreements No. 714005 (ERC StG Q-DIM-SIM), No. 820374 (MetaboliQs), and No. 828946 (PATHOS), and has been supported in part by the Ministry of Science and Technology, Israel. Y.R. is grateful for the support from the Kaye Einstein Scholarship and from the CAMBR fellowship.
© 2021 Published by the American Physical Society