From enhanced paramagnetism to ferromagnetism: the physical properties of Sr$_{\mathrm{1-x}}$La$_{\mathrm{x}}$Co$_{\mathrm{2}}$As$_{\mathrm{2}}$ single crystals

ORAL

Abstract

We have successfully synthesized Sr$_{\mathrm{1-x}}$La$_{\mathrm{x}}$Co$_{\mathrm{2}}$As$_{\mathrm{2}}$ single crystals and characterized them through transport and thermodynamic measurements. The enhanced paramagnet SrCo$_{\mathrm{2}}$As$_{\mathrm{2}}$, which has stripe antiferromagnetic fluctuations, shows a metamagnetic phase transition at a critical magnetic field of 2 T at 2 K. When La is doped into the system, the critical field is suppressed to lower field and itinerant ferromagnetism starts building up at x$=$0.4, rising to a TM of \textasciitilde 200 K at x$=$1. The competition between the stripe spin fluctuations and the itinerant ferromagnetism makes Sr$_{\mathrm{1-x}}$La$_{\mathrm{x}}$Co$_{\mathrm{2}}$As$_{\mathrm{2}}$ compounds a particularly interesting system for the study of itinerant magnetism.

*Work at UCLA was supported by the U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences (BES) under Award Number DE-SC0011978.

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Authors

  • Jie Xing

    • Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA

  • Ni Ni

    • Department of Physics and Astronomy and California NanoSystems Institute, University of California, Los Angeles, CA 90095, USA
    • University of California Los Angeles
    • University of California, Los Angeles