Short-range antiferromagnetic ordering with spiral structure in the finite-doping regime

Abstract

From an itinerant approach, it is found that the commensurate long-range antiferromagnetic (AF) state becomes unstable upon doping against a short-range AF state with spiral structure in the high-${\mathit{T}}_{\mathit{c}}$ copper oxide materials. Such a spiral state is closely related to a fictitious long-range AF state through a local canonical transformation described by a so-called spiral field. The spiral field is stabilized through its coupling with the doped holes, which gain the dominant kinetic energy from the twist state. It is found that the long-wavelength fluctuation of the spiral field, which is induced by the density fluctuation of the holes, will result in an exponential decay of the spin-spin correlation in the scale of hole-hole distance. The distribution of holes in the magnetic zone favors the nodeless p-wave pairing of spin bags, which are present in the local AF order when the latter’s scale is larger than the coherence length ξ.