Phase coexistence, magnetic inhomogeneity, and disorder in the charge-ordered state of Pr2/3Ca1/3MnO3

The coexistence of ferromagnetic metallic and antiferromagnetic charge-orde red (CO) States in Pr2/3Ca1/3MnO3 has been investigated using zero-field mu on spin relaxation, neutron diffraction, calorimetric, and magnetic measure ments. Calorimetric data evidence a high degree of disorder below the CO tr ansition. The data are consistent with large antiferromagnetic (AFM) CO reg ions containing structural and magnetic inhomogeneities densely scattered. Below the charge order temperature (T(CO)approximate to 220 K) the dominant relaxation mechanism of the muon polarization is based on ferromagnetic Mn -Mn correlations and the spin-lattice relaxation rate is peaked at T-C inst ead of T-N. The results agree with a spatial distribution of ferromagnetic and AFM regions strongly interpenetrated. The presence of local magnetic or der in the whole sample is only achieved just below T(C)approximate to 120 K.