Hopping Parameter Expansion for Heavy-Light Systems
  We present a technique which permits the calculation of two-point functions of operators containing one heavy quark and an arbitrary number of light quarks as analytic functions of the heavy-quark mass. It is based on the standard Jacobi linear solver used for the calculation of quark propagators. Results for the heavy-light pseudoscalar and vector meson masses are obtained on 16^3x48 lattices at beta = 6.2 using the Wilson fermion action, and agree with published data. The incorporation of smeared operators and $O(a)$-improved actions presents no problems. 
D.S. Henty and R.D. Kenway