INCOMMENSURATE STRIPE ORDER IN LA2-XSRXNIO4 WITH X=0.225

摘要: In recent studies of La{sub 2{minus}{ital x}}Sr{sub {ital x}}NiO{sub 4} it has been suggested that ordering the dopant-induced holes occurs only commensurately at special values x}, such as 1/3 and 1/2. Commensurate order both charge spin densities also found in a crystal with x}=0.20. The present neutron scattering study an x}=0.225 demonstrates can be incommensurate. fact, incommensurability is temperature dependent, observed previously 2}NiO{sub 4.125}, indicating behavior intrinsic to doped NiO{sub 2} layers not dependent on dopant ions. A careful analysis unusual variation peak widths function momentum transfer perpendicular planes shows charge- spin-density modulations are tied lattice, shift phase from one layer next equal exactly in-plane lattice spacing. comparison results for number samples temperatures vary linearly hole concentration, always occurring higher temperature, clearly driven bymore » charge. {copyright} 1996 American Physical Society.}« less