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arXiv · 1207.2623

Photoinduced Perturbations of the Magnetic Superexchange in Core-Shell Prussian Blue Analogues

Elisabeth S. Knowles·Matthieu F. Dumont·Marcus K. Peprah·Mark W. Meisel·Carissa H. Li·Matthew J. Andrus·Daniel R. Talham
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Abstract

Cubic heterostructured (BA) particles of Prussian blue analogues, composed of a shell of ferromagnetic K_{0.3}Ni[Cr(CN)_6]_{0.8} \cdot 1.3H_2O (A), Tc ~ 70 K, surrounding a bulk core of photoactive ferrimagnetic Rb_{0.4}Co[Fe(CN)_6]_{0.8} \cdot 1.2H_2O (B), Tc ~20 K, have been studied. Below Tc ~ 70 K, these samples exhibit a persistent photoinduced decrease in low-field magnetization, and these results resemble data from other core-shell particles and analogous ABA heterostructured films. This net decrease suggests that the photoinduced lattice expansion in the B layer generates a strain-induced decrease in the magnetization of the A layer, similar to a pressure-induced decrease observed by others in a pure A-like material and by us in our BA cubes. Upon further examination, the data also reveal a significant portion of the A material whose superexchange, J, is perturbed by the photoinduced strain from the B constituent.

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Elisabeth S. Knowles, Matthieu F. Dumont, Marcus K. Peprah, Mark W. Meisel, Carissa H. Li, Matthew J. Andrus, Daniel R. Talham. 2012-07-11. Photoinduced Perturbations of the Magnetic Superexchange in Core-Shell Prussian Blue Analogues. https://arxiv.org/abs/1207.2623

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