Fig. 2: The isothermal magnetic field-dependent magnetization at various temperatures.
From: Magnetic properties of intercalated quasi-2D Fe3-xGeTe2 van der Waals magnet

a shows a comparison between fully paramagnetic pristine (black) and the room temperature ferromagnetic behavior of intercalated (red) FGT. b, c display the ferromagnetic ordering of intercalated FGT up to 350 K.