Magnetic properties, resistivity, and heat capacity of EuMnO3 and Eu0.7A0.3MnO3 (A = Ca, Sr) compounds

We present magnetic-, resistivity-, and specific-heat measurements of the title compounds and found that in Eu0.7Sr0.3MnO3 an insulator-metal transition can be induced by an external field below 60 K while Eu0.7Ca0.3MnO3 remains insulating. EuMnO3 exhibits two magnetic transitions at 35 and 47 K which are associated with the appearance of a weak ferromagnetic component and antiferromagnetic ordering, With respect to the parent compound, Ca and Sr substitution enhance the ferromagnetic component significantly, however, for low fields and after zero-field cooling the antiferromagnetic ground state is preserved to a large extent. (C) 1998 American Institute of Physics. [S0021-8979(98)26711-9].