Anisotropy of magnetic properties of Fe1+y Te
2014 (English)In: Journal of Physics: Condensed Matter, ISSN 0953-8984, E-ISSN 1361-648X, Vol. 26, no 43, 436003- p.Article in journal (Refereed) Published
The magnetic properties of Fe1+y Te single crystals (y similar or equal to 0.1 divided by 0.18) were studied at temperatures 4.2 divided by 300 K. At an ambient pressure, with decreasing temperature a drastic drop in chi(T) was confirmed at T similar or equal to 60 divided by 65 K, which appears to be closely related to the antiferromagnetic (AFM) ordering. It is found that the magnitudes of the anisotropy of magnetic susceptibility Delta chi. in the AFM phase are close in the studied samples, whereas the sign of the anisotropy apparently depends on the small variations of the excess iron y in Fe1+y Te samples. The performed DFT calculations of the electronic structure and magnetic properties for the stoichiometric FeTe compound indicate the presence of frustrated AFM ground states. There are very close energies and magnetic moments for the double stripe configurations, with the AFM axes oriented either on the basal plane or along the [0 0 1] direction. Presumably, both these configurations can be realized in Fe1+y Te single crystals, depending on the variations of the excess iron. This can provide different signs of magnetic anisotropy in the AFM phase, presently observed in the Fe1+y Te samples. For these types of AFM configuration, the calculations for the FeTe values of Delta chi are consistent with our experimental data.
Place, publisher, year, edition, pages
2014. Vol. 26, no 43, 436003- p.
Fe-based superconductors, magnetic anisotropy, magnetic susceptibility, FeTe, electronic structure
IdentifiersURN: urn:nbn:se:uu:diva-237295DOI: 10.1088/0953-8984/26/43/436003ISI: 000343643600018PubMedID: 25299131OAI: oai:DiVA.org:uu-237295DiVA: diva2:767580