Field-Induced Order in Heavy-Fermion Compound YbCo₂Zn₂₀

Abstract

The field-induced ordered phase of heavy-fermion compound YbCo 2 Zn 20 was investigated by means of single crystal neutron diffraction. At an applied field of 11.8 T along the [11 1] direction, a superlattice peak was found at (3 21 2 1 2 ) at 200 mK, whereas no peak was detected at q=(1 0 0). In addition, broad diffuse scattering was revealed around induced superlattice peak. The present result evidences that the field-induced ordered phase has different character to the pressure induced antiferromagnetic ordered phase.