Electronic Self-Organization in the Single-Layer Manganite Pr1-xCa1+xMnO4

Neutron Scattering Science Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831-6393, USA.
Physical Review Letters (Impact Factor: 7.51). 10/2009; 103(16):167202. DOI: 10.1103/PhysRevLett.103.167202
Source: arXiv


We use neutron scattering to investigate the doping evolution of the magnetic correlations in the single-layer manganite Pr1-xCa1+xMnO4, away from the x=0.5 composition where the CE-type commensurate antiferromagnetic (AF) structure is stable. We find that short-range incommensurate spin correlations develop as the system is electron doped (x<0.5), which coexist with the CE-type AF order. This suggests that electron doping in this system induces an inhomogeneous electronic self-organization, where commensurate AF patches with x=0.5 are separated by electron-rich domain walls with short-range magnetic correlations. This behavior is strikingly different than for the perovskite Pr1-xCaxMnO3, where the long-range CE-type commensurate AF structure is stable over a wide range of electron or hole doping around x=0.5.

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