Publication Type
Journal
Journal Name
Physical Review Letters
Publication Date
Page Number
197203
Volume
122
Issue
19
Abstract
We report the discovery of incommensurate magnetism near quantum criticality in CeNiAsO through neutron scattering and zero field muon spin rotation. For T<TN1=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<TN2=7.6(3) K, we find coplanar commensurate order with a moment of 0.37(5)μB, reduced to 30% of the saturation moment of the |±12⟩ Kramers doublet ground state, which we establish through inelastic neutron scattering. Muon spin rotation in CeNiAs1−xPxO shows the commensurate order only exists for x≤0.1 so we infer the transition at xc=0.4(1) is between an incommensurate longitudinal spin density wave and a paramagnetic Fermi liquid.
