Magnetic structures and magnetic phase transitions in the Mn-doped orthoferrite TbFeO studied by neutron powder diffraction
arXiv:1602.00939 · doi:10.1063/1.4940958
Abstract
The magnetic structures and the magnetic phase transitions in the Mn-doped orthoferrite TbFeO studied using neutron powder diffraction are reported. Magnetic phase transitions are identified at 295~K where a paramagnetic-to-antiferromagnetic transition occurs in the Fe/Mn sublattice, 26~K where a spin-reorientation transition occurs in the Fe/Mn sublattice and 2~K where Tb-ordering starts to manifest. At 295~K, the magnetic structure of the Fe/Mn sublattice in TbFeMnO belongs to the irreducible representation ( or ). A mixed-domain structure of () is found at 250~K which remains stable down to the spin re-orientation transition at 26~K. Below 26~K and above 250~K, the majority phase () is that of . Below 10~K the high-temperature phase remains stable till 2~K. At 2~K, Tb develops a magnetic moment value of 0.6(2)~f.u. and orders long-range in compatible with the representation. Our study confirms the magnetic phase transitions reported already in a single crystal of TbFeMnO and, in addition, reveals the presence of mixed magnetic domains. The ratio of these magnetic domains as a function of temperature is estimated from Rietveld refinement of neutron diffraction data. Indications of short-range magnetic correlations are present in the low- region of the neutron diffraction patterns at . These results should motivate further experimental work devoted to measure electric polarization and magnetocapacitance of TbFeMnO.
16 pages, 7 figures, Accepted to J. Appl. Phys., 2016