Investigation of the field-treated magnetic state in Gd5Ge4
  At low temperatures, the intermetallic compound Gd$_5$Ge$_4$ shows a sharp field-induced transition into a ferromagnetic state around 25 kOe of applied field. The material remains in the field treated ferromagnetic state even when the magnetic field is removed. We have investigated the character of this field-treated state by magnetization and heat capacity measurements. The nature of the magnetization and the heat capacity are found to be different above and below a charactersitic temperature Tirr = 25 K. 
S. Majumdar, S. J. Crowe, D. McK. Paul, M. R. Lees, V. Hardy