Incommensurate Magnetism Near Quantum Criticality in CeNiAsO

Shan Wu; W A Phelan; L Liu; J R Morey; J A Tutmaher; J C Neuefeind; Ashfia Huq; Matthew B Stone; M Feygenson; David W Tam; Benjamin A Frandsen; Benjamin Trump; Cheng Wan; S R Dunsiger; T M McQueen; Y J Uemura; C L Broholm

doi:10.1103/PhysRevLett.122.197203

Incommensurate Magnetism Near Quantum Criticality in CeNiAsO

Phys Rev Lett. 2019 May 17;122(19):197203. doi: 10.1103/PhysRevLett.122.197203.

Authors

Shan Wu^{1

2}, W A Phelan¹, L Liu³, J R Morey¹, J A Tutmaher¹, J C Neuefeind⁴, Ashfia Huq⁵, Matthew B Stone⁵, M Feygenson⁶, David W Tam⁷, Benjamin A Frandsen⁸, Benjamin Trump⁹, Cheng Wan¹, S R Dunsiger¹⁰, T M McQueen^{1

11}, Y J Uemura³, C L Broholm^{1

5

11}

Affiliations

¹ Department of Physics and Astronomy and Institute for Quantum Matter, Johns Hopkins University, Baltimore, Maryland 21218, USA.
² Department of Physics, University of California Berkeley, Berkeley, California 94720, USA.
³ Department of Physics, Columbia University, New York, New York 10027, USA.
⁴ Oak Ridge National Laboratory, Chemical and Engineering Materials Division, Oak Ridge, Tennessee 37831, USA.
⁵ Oak Ridge National Laboratory, Neutron Scattering Division, Oak Ridge, Tennessee 37831, USA.
⁶ Juelich Centre for Neutron Science, Forschungszentrum Juelich GmbH, 52425 Juelich, Germany.
⁷ Department of Physics and Astronomy, Rice University, Houston, Texas 77005, USA.
⁸ Department of Physics and Astronomy, Brigham Young University, Provo, Utah 84602, USA.
⁹ NIST Center for Neutron Research, National Institute of Standards and Technology, Gaithersburg, Maryland 20899, USA.
¹⁰ Department of Physics, Simon Fraser University, Burnaby, British Columbia, Canada V5A 1S6.
¹¹ Department of Materials Science and Engineering, Johns Hopkins University, Baltimore, Maryland 21218, USA.

Abstract

We report the discovery of incommensurate magnetism near quantum criticality in CeNiAsO through neutron scattering and zero field muon spin rotation. For T<T_{N1}=8.7(3) K, a second order phase transition yields an incommensurate spin density with a wave vector k=(0.44(4),0,0). For T<T_{N2}=7.6(3) K, we find coplanar commensurate order with a moment of 0.37(5)μ_{B}, reduced to 30% of the saturation moment of the |±1/2⟩ Kramers doublet ground state, which we establish through inelastic neutron scattering. Muon spin rotation in CeNiAs_{1-x}P_{x}O shows the commensurate order only exists for x≤0.1 so we infer the transition at x_{c}=0.4(1) is between an incommensurate longitudinal spin density wave and a paramagnetic Fermi liquid.

Grants and funding

9999-NIST/ImNIST/Intramural NIST DOC/United States