Experimental phase boundary between quantum critical and quantum disordered regime in hole-doped La$_2$CuO$_4$

ORAL

Abstract

The long-range antiferromagnetic order in La$_2$CuO$_4$ is suppressed by hole doping at $x_c\approx 3\%$ of Li dopant concentration. This allows experimental investigation of the spin fluctuations near the quantum critical point of a 2-dimensional $S$=1/2 antiferromagnet. According to quantum critical theory, the quantum critical (QC) $E/T$ scaling is expected to break down and crosses over to a constant energy quantum disordered (QD) scaling at low temperatures when the doping $x>x_c$. In this single crystal inelastic cold neutron scattering study on spin dynamics of La$_2$Cu$_{1-x}$Li$_{x}$O$_4$ (0.04$

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Authors

  • Ying Chen

    University of Maryland/NIST

  • Wei Bao

    Los Alamos National Laboratory, Los Alamos National Laboratory, Los Alamos, NM 87545

  • Emilio Lorenzo

    CNRS, France

  • Anne Stunault

    Institut Laue-Langevin, France

  • John L. Sarrao

    Los Alamos National Laboratory, Los Alamos National Lab, LANL, Condensed Matter and Thermal Physics, Los Alamos National Laboratory

  • Sungil Park

    Korea Atomic Energy Research Institute

  • Yiming Qiu

    University of Maryland/NIST