Anomalous critical exponents in itinerant ferromagnets Ni1-xRhx (x = 0.3 - 0.375) close to a quantum phase transition

ORAL

Abstract

We studied the critical behavior of itinerant ferromagnets Ni1-xRhx with x = 0.3 - 0.375 based on the Arrott-Noakes scaling analysis. The ferromagnetic ordering temperature is continuously suppressed to zero at a critical concentration xc ~ 0.375. For x = 0.3, mean-field like exponents β ~ 0.5,γ ~ 1.5, and δ ~ 3 are observed. With increasing x, critical exponents vary smoothly and reach at β ~ 0.6,γ ~ 0.7, and δ ~ 2.3 for x = 0.37. The evolution of exponents with x and the exponent values close to xc cannot be described by any known universality class for classical models. The possible explanation for the trend of exponents is that, close to xc, strong quantum fluctuations enhance the role of disorder and drive the system to a new strong-coupling regime.

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Presenters

  • Chien-Lung Huang

    Rice University, Physics and Astronomy, Rice University, Department of Physics and Astronomy, Rice University

Authors

  • Chien-Lung Huang

    Rice University, Physics and Astronomy, Rice University, Department of Physics and Astronomy, Rice University

  • Bianca Spiess

    Physics and Astronomy, Rice University

  • Sebastian Kuntz

    Institute fuer Festkoerperphysik, Karlsruhe Institute of Technology

  • Kai Grube

    Karlsruhe Institute of Technology, Institute fuer Festkoerperphysik, Karlsruhe Institute of Technology

  • Alannah Hallas

    Physics and Astronomy, Rice University, Rice University

  • Kyle Bayliff

    Physics and Astronomy, Rice University

  • Tiglet Besara

    National High Magnetic Field Laboratory

  • Theo Siegrist

    National High Magnetic Field Laboratory, Florida State University

  • Yipeng Cai

    Department of Physics and Astronomy, McMaster University, McMaster University

  • James Beare

    Physics and Astronomy, McMaster University, Department of Physics and Astronomy, McMaster University, McMaster University

  • Graeme Luke

    Department of Physics, McMaster University, Physics and Astronomy, McMaster University, McMaster University, Department of Physics and Astronomy, McMaster University

  • Emilia Morosan

    Rice University, Physics and Astronomy, Rice University, Department of Physics and Astronomy, Rice University