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arXiv · 1104.1571

Neutron scattering study of magnetic phase separation in nanocrystalline La$_{5/8}$Ca$_{3/8}$MnO$_3$

Chetan Dhital·Clarina de la Cruz·C. Opeil·A. Treat·K. F. Wang·J. -M. Liu·Z. F. Ren·Stephen D. Wilson
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Abstract

We demonstrate that magnetic phase separation and competing spin order in the colossal magnetoresistive (CMR) manganites can be directly explored via tuning strain in bulk samples of nanocrystalline La$_{1-x}$Ca$_x$MnO$_3$. Our results show that strain can be reversibly frozen into the lattice in order to stabilize coexisting antiferromagnetic domains within the nominally ferromagnetic metallic state of La$_{5/8}$Ca$_{3/8}$MnO$_3$. The measurement of tunable phase separation via magnetic neutron powder diffraction presents a direct route of exploring the correlated spin properties of phase separated charge/magnetic order in highly strained CMR materials and opens a potential avenue for realizing intergrain spin tunnel junction networks with enhanced CMR behavior in a chemically homogeneous material.

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Chetan Dhital, Clarina de la Cruz, C. Opeil, A. Treat, K. F. Wang, J. -M. Liu, Z. F. Ren, Stephen D. Wilson. 2011-04-08. Neutron scattering study of magnetic phase separation in nanocrystalline La$_{5/8}$Ca$_{3/8}$MnO$_3$. https://doi.org/10.1103/physrevb.84.144401

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