Griffiths phase behaviour in a frustrated antiferromagnetic intermetallic compound

摘要

The rare coexistence of a Griffiths phase (GP) and a geometrically frustrated antiferromagnetism in the non-stoichiometric intermetallic compound GdFe_0.17Sn₂ (the paramagnetic Weiss temperature θ _p?~??59?K) is reported in this work. The compound forms in the Cmcm space group with large structural anisotropy ( b / c ~?4). Interestingly, all the atoms in the unit cell possess the same point group symmetry (Wycoff position 4 c ), which is rather rare. The frustration parameter, f?=?| θ _p|/T_N has been established as 3.6, with the N é el temperature T_N and Griffiths temperature T_G being 16.5 and 32?K, respectively. The T_G has been determined from the heat capacity measurement and also from the magnetocaloric effect (MCE). It is also shown that substantial difference in GP region may exist between zero field and field cooled measurements - a fact hitherto not emphasized so far.