Magnon-mediated NMR quantum gates in a 1-D antiferromagnet
  We propose a method of controlling a quantum logic gate in a solid-state NMR quantum computer. A switchable inter-qubit coupling can be generated by using the longitudinal component of the Suhl-Nakamura interaction induced by a local singlet-triplet excitation in a 1-D antiferromagnet with a spin gap. 
Atsushi Goto, Tadashi Shimizu, Kenjiro Hashi