Ultrasharp Magnetization Steps in Perovskite Manganites

Department of Physics and Materials Research Institute, Pennsylvania State University, University Park, Pennsylvania 16802, USA.
Physical Review Letters (Impact Factor: 7.51). 12/2002; 89(28 Pt 1):286602. DOI: 10.1103/PhysRevLett.89.286602
Source: PubMed


We report a detailed study of steplike metamagnetic transitions in polycrystalline Pr0.5Ca0.5Mn0.95Co0.05O3. The steps have a sudden onset below a critical temperature, are extremely sharp (width <2x10(-4) T), and occur at critical fields which are linearly dependent on the absolute value of the cooling field in which the sample is prepared. Similar transitions are also observed at low temperature in non-Co doped manganites, including single crystal samples. These data show that the steps are an intrinsic property, qualitatively different from either previously observed higher temperature metamagnetic transitions in the manganites or metamagnetic transitions observed in other materials.

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    • "In fact, the step-like behaviors are usually observed in the systems that CO AFM states coexist with a spin-glass-like state or a short range FM order state. The origin of this phenomenon is still a matter of controversy [18], but the pictures of field-dependent CO and the jerky growth of FM fraction in a phase-separation system have been accepted [11] [12] [19] [20]. In previous studies, the martensitic-like transformation scenario has been proposed to explain the temperature-dependent properties [21] [22] [23]. "
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