Field-induced magnetic states in geometrically frustrated SrEr2O4

We report an unusual in-field behaviour of SrEr _2 2 O _4 />4 for a magnetic field applied along two high-symmetry directions, the and c axes. This geometrically frustrated magnet hosts crystallographically inequivalent Er ions, Er1 Er2, that are both located on triangular zigzag ladders, but only one site, Er1, forms long-range order at low temperatures in zero field. follow sequence peculiar induced states with detailed single-crystal magnetisation neutron diffraction experiments. On application external display="inline">c axis, antiferromagnetic ions is rapidly destroyed replaced, fields between 2 5 kOe, by state shorter-range correlations. The change correlation length coincides fast increase during metamagnetic transition above which reestablished maintained into high fields. high-field ferromagnet-like characterised significantly different moments sites, site dominating process. For parallel to range 4 12 planes diffuse scattering observed due one-dimensional correlations Er2 replaced much more localised still features corresponding establishment up-up-down structure associated one-third plateau. Above 14 following another phase transition. this direction field, dictate succession transitions while remain less polarised. A complete polarisation sites not achieved even 50~kOe either direction, reflecting strongly anisotropic nature process .