Observation of a Griffiths phase in paramagnetic La$_{1-x}$Sr$_x$MnO$_3$

ORAL

Abstract

We report on the discovery of a new phase boundary above the magnetic ordering temperature in low doped La$_{1-x} $Sr$_x$MnO$_3$ by means of ESR and susceptibility measurements. The observed triangular phase regime in the paramagnetic state is identified as a realization of a Griffiths phase, where disorder in the ferromagnetic bonds leads to the existence of a temperature scale above $T_C$. The influence of quenched disorder to allow for the occurrence of a Griffiths phase becomes evident by its appearance within the Jahn-Teller distorted orthorhombic structure.

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Authors

  • Joachim Deisenhofer

  • Hans-Albrecht Krug von Nidda

  • Joachim Hemberger

  • Alois Loidl

    • EP~V, Center for Electronic Correlation and Magnetism, University of Augsburg, 86135~Augsburg, Germany

  • Daniel Braak

    • TP~II, Institute for Physics, University of Augsburg, 86135 Augsburg, Germany

  • Rushana Eremina

  • Vladimir Ivanshin

    • Kazan State University, 420008 Kazan, Russia

  • Anatoli Balbashov

    • Moscow Power Engineering Institute, 105835 Moscow, Russia

  • Tsuyoshi Kimura

    • Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan

  • Yoshinori Tokura

    • Department of Applied Physics, University of Tokyo, Tokyo 113-8656, Japan