  We derive a theory for the generation of arbitrary spin-spin interactions in
superconducting circuits via periodic time modulation of the individual qubits
or the qubit-qubit interactions. The modulation frequencies in our approach are
in the microwave or radio frequency regime so that the required fields can be
generated with standard generators. Among others, our approach is suitable for
generating spin lattices that exhibit quantum spin liquid behavior such as
Kitaev's honeycomb model.
