Interacting electrons with a square Fermi surface are investigated from a bosonic point of view taking into account electron scattering between all faces of the square. Fermion operators are classified according to their dimensions and the stability of the boson fixed-point is investigated. In particular we find, in contrast to previous studies, that the square Fermi surface is unstable to doping in the case of no spin gap and microscopic Hubbard interactions.
机构:
NASA, George C Marshall Space Flight Ctr, Biophys Grp, Huntsville, AL 35812 USANASA, George C Marshall Space Flight Ctr, Biophys Grp, Huntsville, AL 35812 USA