O(a) improvement of 2D N=(2,2) lattice SYM theory

We perform a tree-level O(a) improvement of two-dimensional N=(2,2) supersymmetric Yang–Mills theory on the lattice, motivated by the fast convergence in numerical simulations. The improvement respects an exact supersymmetry Q which is needed for obtaining the correct continuum limit without a parameter fine tuning. The improved lattice action is given within a milder locality condition in which the interactions are decaying as the exponential of the distance on the lattice. We also prove that the path-integral measure is invariant under the improved Q-transformation.