Modeling magnetic fluctuations in the stripe ordered state

In this work we study the magnetic behavior of a simple model of the stripe ordered phase of the cuprates, an array of alternating coupled doped and undoped two-leg Hubbard-type ladders. To obtain the coupled ladders' magnetic response, we employ available dynamical susceptibilities of the individual two-leg ladders and treat the interladder coupling in a random phase approximation. Strikingly, we find two possible scenarios for the ordered state induced by the coupling between ladders: the spin modulation may both occur in the conventional fashion, perpendicular to the direction of the stripes, but it may also occur parallel to the stripe direction. These two scenarios are differentiated according to different microscopic realizations of the component doped ladders. We argue that inelastic neutron scattering experiments on two stripe ordered cuprates, La1.875Ba0.125CuO4 and La2-xSrxCuO4 at x similar to 0.125, do not readily distinguish between these scenarios due to manner in which stripes form in these materials.