Spin bits at two loops
  We consider the Super Yang--Mills/spin system map to construct the SU(2) spin bit model at the level of two loops in Yang--Mills perturbation theory. The model describes a spin system with chaining interaction. In the large $N$ limit the model is shown to be reduced to the two loop planar integrable spin chain. 
S. Bellucci, P.-Y. Casteill, A. Marrani, and C. Sochichiu