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Field-induced avalanche to the ferromagnetic state in the phase-separated ground state of manganites

F. M. Woodward·J. W. Lynn·M. B. Stone·R. Mahendiran·P. Schiffer·J. F. Mitchell·D. N. Argyriou·L. C. Chapon
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Abstract

Perovskite manganite compounds such as Pr_(1-x)(Ca_(1-y)Sr_y)_xMn3 can be tuned to exhibit a metastable ground state where two magnetic/crystallographic phases coexist in zero magnetic field. Field-dependent neutron diffraction measurements on both poly- and single-crystal samples with a range of Pr, Ca, and Sr dopings(0.3<x<0.35 and y<0.30) reveal that the charge-ordered, antiferromagnetic phase of the ground state suddenly and irreversibly jumps to the ferromagnetic state. The transition occurs spontaneously at some time after the field is set above a threshold field, indicating that once the transition is initiated an avalanche occurs that drives it to completion.

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F. M. Woodward, J. W. Lynn, M. B. Stone, R. Mahendiran, P. Schiffer, J. F. Mitchell, D. N. Argyriou, L. C. Chapon. 2004-04-07. Field-induced avalanche to the ferromagnetic state in the phase-separated ground state of manganites. https://doi.org/10.1103/physrevb.70.174433

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