Classification of minimally doubled fermions

We propose a method to control the number of species of lattice fermions, which yields new classes of minimally doubled lattice fermions. We show it is possible to control the number of species by handling O(a) Wilson-term-like corrections in fermion actions, which we will term "twisted-ordering method". Using this method we obtain new minimally doubled actions with one exact chiral symmetry and exact locality. We classify the known minimally doubled fermions into two types based on the locations of the propagator poles in the Brillouin zone.