New Type of the Domain-Redistribution at Low Magnetic Fields in Phase II of CeB6

Abstract

We performed the detailed investigation of the magnetization ( M ) of CeB 6 at low magnetic fields in the O x y -type antiferro-quadrupole (AFQ) ordered phase II to clarify the mechanism of the domain redistribution by magnetic field. Although M in phase II is isotropic above ∼1 kOe, it is anisotropic at lower magnetic fields and the magnetic field of the domain redistribution ( H c IIA–IIB ) is highly anisotropic. M [001] H c IIA–IIB[110] > H c IIA–IIB[111] . Here, M [001] and H c IIA–IIB[001] are M and H c IIA–IIB for H ∥[001], etc. respectively. Although there exist three domains of O x y -, O y z -, and O z x -AFQ ordered states at H =0 as in a usual AF magnet, these domains are coupled in magnetic fields and the single domain state is formed by the linear combination of O x y , O y z , and O z x quadrupole moments above H c IIA–IIB through the magnetic field induced higher order T x y z -antiferro-octupole (AFO) interaction. The domain redistribution takes p...