Large Wilson loops with overlap and clover fermions: Two-loop evaluation of the b-quark mass shift and the quark–antiquark potential

We compute, to two loops in perturbation theory, the fermionic contribution to rectangular R×TR×T Wilson loops, for different values of R and T  . We use the overlap fermionic action. We also employ the clover action, for comparison with existing results in the literature. In the limit R,T→∞R,T→∞ our results lead to the shift in the static quark energy, which can be used to determine the b-quark mass. We also evaluate the perturbative static potential as T→∞T→∞.