Large reversible magnetocaloric effect in TbCoC2 in low magnetic field

A large reversible negative magnetic-entropy change Delta S-M has been observed in TbCoC2, accompanied by a second-order phase transition at 28 K. The maximum value of -Delta S-M is 15.3 J kg(-1) K-1 at 30 K for a magnetic-field change from 0 to 5 T, with the refrigerant capacity of 354 J kg(-1). In particular, also the large -Delta S-M(max) of 7.8 J kg(-1) K-1, is obtained for a small field change from 0 to 2 T. The large reversible Delta S-M and the high reversible refrigerant capacity in low magnetic field indicate that TbCoC2 may be a promising candidate for magnetic refrigeration at low temperatures. (C) 2008 American Institute of Physics.