Superconductivity, Spin Density Wave and Field Induced Spin Density Wave versus anion ordering in the (TMTSF)2ClO4 salt

Abstract

We study the effect of the ClO4 anion ordering on the superconducting (SC) and Spin Density Wave (SDW) phases of the (TMTSF)2ClO4.. Based on a renormalizationgroup theory, we find that by suppressing the anion ordering the original SC phase is followed by a coexisting SC/SDW phase which is replaced by a pure SDW state for small values of the anion gap. Moreover, we study, within a mean field theory, the effect of the anion gap on the field induced spin density wave (FISDW) phases at high magnetic field. By analyzing the behavior of these phases, we conclude that the anion gap has to be small compared to the interchain hopping parameter.