Anomalous critical exponents in itinerant ferromagnets Ni<sub>1-<i>x</i></sub>Rh<i><sub>x</sub></i> (<i>x</i> = 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.

*We acknowledge support from the Gordon and Betty Moore Foundation EPiQS Initiative through grant GBMF4417.

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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