Polarized neutron scattering study of the multiple order parameter system NdB

Metoki, Naoto   ; Yamauchi, Hiroki   ; Matsuda, Masaaki*; Fernandez-Baca, J. A.*; Watanuki, Ryuta*; Hagihara, Masato*   

Neutron polarization analysis has been carried out in order to clarify the magnetic structure of multiple order parameter -electron system NdB. We confirmed the non-collinear "all-in all-out" structure () of the in-plane moment. We found that the magnetic moment along the -axis showed diagonally antiferromagnetic structure (). The unusual magnetic ordering is phenomenologically understood via Landau theory. We also found that a long-period incommensurate modulation of the () antiferromagnetic structure of with the propagation = (0.14, 0.14, 0.1) and = (0.2, 0, 0.1) in phase III and IV, respectively. It is clear that the multipole degree-of-freedom based on pseudo-quartet -electron state play important role.