Field-induced avalanche to the ferromagnetic state in the   phase-separated ground state of manganites
  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. 
F. M. Woodward, J. W. Lynn, M. B. Stone, R. Mahendiran, P. Schiffer,   J. F. Mitchell, D. N. Argyriou, L. C. Chapon