Quantum computation and simulation requires 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 coupling, based on superconducting nano-structures designed to channel the magnetic flux created by the qubits. We detail semi-classical 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.
@article{arxiv.2107.05130,
title = {Long range magnetic dipole-dipole interaction mediated by a superconductor},
author = {Yoav Romach and Tal Wasserman and Shai Tishby and Nir Bar-Gill},
journal= {arXiv preprint arXiv:2107.05130},
year = {2021}
}