Accelerating Dynamical Fermion Computations using the Rational Hybrid   Monte Carlo (RHMC) Algorithm with Multiple Pseudofermion Fields
  There has been much recent progress in the understanding and reduction of the computational cost of the Hybrid Monte Carlo algorithm for Lattice QCD as the quark mass parameter is reduced. In this letter we present a new solution to this problem, where we represent the fermionic determinant using (n) pseudofermion fields, each with an (\nth) root kernel. We implement this within the framework of the Rational Hybrid Monte Carlo (RHMC) algorithm. We compare this algorithm with other recent methods in this area and find it is competitive with them. 
M. A. Clark, A. D. Kennedy