A reconfigurable spin ice

Magnetism Spin ices, magnetic systems in which local spins respect the so-called ice rules, can occur in natural materials or be engineered in patterned arrays. King et al. used superconducting qubits to implement a two-dimensional artificial spin ice. By changing the strength and ratio of spin couplings, the researchers were able to access a variety of ground states. Arranging the boundary spins in an antiferromagnetic configuration and then flipping one of those spins generated a magnetic monopole in the system's interior. Science , abe2824, this issue p. [576][1] [1]: /lookup/doi/10.1126/science.abe2824