Competing incommensurate orders in a heavy fermion antiferromagnet CeNiGe<sub>2</sub>

ORAL

Abstract

We have determined the magnetic structure and phase diagram of a heavy fermion compound CeNiGe2 as a function of magnetic field and temperature using single crystal neutron diffraction. At zero field and the base temperature of 0.4 K, CeNiGe2 shows a complex magnetic structure comprising two propagation vectors κ1 = (0.23, 0, 0) and κ2 = (0.18, 0, 0). The intensities observed at several magnetic satellites indicate that the moments are predominantly along the c-axis. At higher temperatures the order parameter corresponding to κ1 (OP1) decreases until it is suppressed at TN1 = 3 K. The order parameter for κ2 (OP2) initially increases with increasing temperature and only begins to decrease above TN1 until it vanishes at TN2 = 4.2 K. A similar but opposite trend in order parameters is observed when a magnetic field is applied along the c-axis. OP2 is suppressed at a lower critical field of Bc2 = 0.75 T, whereas OP1 first increases until it reaches maximum at Bc2 and begins to decrease and vanishes at the critical field of Bc1 = 2.75 T. Taken together, CeNiGe2 provides an interesting platform where competition between two nearby incommensurate orders can be systematically tuned by temperature and magnetic field.

–

Presenters

  • Lekh Poudel

    • NIST Center for neutron research, National Institute of Standard and Technology, Gaithersburg, MD

Authors

  • Lekh Poudel

    • NIST Center for neutron research, National Institute of Standard and Technology, Gaithersburg, MD

  • Yang Zhao

    • University of Maryland - College Park
    • NIST Center for neutron research, National Institute of Standard and Technology, Gaithersburg, MD
    • National Institute of Standards and Technology

  • Zhijun Xu

    • NIST Center for neutron research, National Institute of Standard and Technology, Gaithersburg, MD
    • University of Maryland, College Park and NIST
    • National Institute of Standards and Technology

  • William Ratcliff

    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • National Institute of Standards and Technology
    • NIST Center for neutron research, National Institute of Standard and Technology, Gaithersburg, MD
    • NIST

  • Johnpierre Paglione

    • Physics, University of Maryland
    • University of Maryland, College Park
    • Center for Nanophysics and Advanced Materials, University of Maryland College Park
    • Center for Nanophysics and Advance Materials, University of Maryland, College Park, MD
    • University of Maryland, College Park & NIST
    • Department of Physics, University of Maryland, College Park
    • University of Maryland
    • University of Maryland - College Park

  • Jeffrey W Lynn

    • National Institute of Standards and Technology
    • NIST
    • NIST Center for Neutron Research, National Institute of Standards and Technology
    • NIST Center for neutron research, National Institute of Standard and Technology, Gaithersburg, MD