Spin-orbit coupling and spirals in dopedLa2CuO4

Abstract
Spin-orbit coupling in doped La2 CuO4 can result in (1) a novel electron-phonon coupling involving soft oxygen ‘‘tilting’’ phonons, and (2) stabilization of a commensurate antiferromagnetic state over a spiral state in the presence of a sufficiently large tilt distortion. This second effect may be responsible for the unusual electronic properties of La1.88 Ba0.12 CuO4.