Under zero magnetic field, a quadrupolar order parameter at qQ = (1/2, 1/2, 1/2) in a typical antiferro-quadrupole (AFQ) ordering compound CeB6 has been observed for the first time by means of a resonant X-ray scattering (RXS) technique. The RXS is observed at the 2p → 5d dipole transition energy of the Ce L3-edge. Using this RXS technique to observe the pure order parameter of the AFQ state, the magnetic phase diagram of Phase II is first determined.
- Antiferro-quadrupole ordering
- Magnetic phase diagram
- Orbital ordering
- Resonant X-ray scattering