Interesting thermomagnetic history effects in the antiferromagnetic   state of SmMn_2Ge_2
  We present results of magnetization measurements showing that the magnetic response of the antiferromagnetic state of SmMn_2Ge_2 depends on the path used in the field(H)-temperature(T) phase space to reach this state. Distinct signature of metastablity is observed in this antiferromagnetic state when obtained via field-cooling/field-warming paths. The isothermal M-H loops show lack of end-point memory, reminiscent of that seen in metastable vortex states near the field-induced first order phase transition in various type-II superconductors. 
S. B. Roy, S. Chaudhary, M. K. Chattopadhyay, P. Chaddah and E. V.   Sampathkumaran