Paramagnetic fluctuations in Pr0.65Ca0.35MnO3 around the charge-ordering temperature

We have studied the ferromagnetic and antiferromagnetic fluctuations in the charge-ordered Pr0.65Ca0.35MnO3 antiferromagnet by triple-axis neutron spectrometry. Whereas ferromagnetic fluctuations are observed above and below the charge-ordering transition (TCO), the antiferromagnetic fluctuations develop only below TCO .T he dynamical exponent z of both ferromagnetic and antiferromagnetic fluctuations are determined. The ferromagnetic fluctuations are not completely suppressed below TCO and their correlation lengths are short-ranged at all temperatures. The results are discussed with respect to the Zener polaron model recently introduced to describe the charge-ordered state of Pr0.6Ca0.40MnO3.