Flip of spin helix chirality and ferromagnetic state in Fe1−xCoxGe compoundsстатья
Статья опубликована в высокорейтинговом журнале
Информация о цитировании статьи получена из
Web of Science,
Scopus
Статья опубликована в журнале из списка Web of Science и/или Scopus
Дата последнего поиска статьи во внешних источниках: 2 апреля 2015 г.
Аннотация:We have synthesized the solid solutions of Fe1−xCoxGe compounds with x running from 0.0 to 0.9. Small-angle neutron scattering and magnetization measurements have shown that these compounds are ordered into the spin helix structure below the critical temperature Tc. The helix is transformed into the ferromagnet by application of the magnetic field above the critical value Hc2. It is shown that Tc decreases smoothly with concentration x from
280 K for FeGe to 0 for CoGe. The values of the helix wave vector ks and the critical field Hc2 depend stronglyon concentration x, firstly, decreasing from pure FeGe to its minimum (|ks| → 0, Hc2 → 0) at xc ≈ 0.6, and, then increasing again at higher x. Thus, we observe a transformation of the helix structure to the ferromagnet at x → xc at zero field. We concluded that this transformation is caused by different signs of the spin helicity for
the compounds with x > xc and x < xc. We believe that the mechanism of the transformation is caused by the competition between the Dzyaloshinskii-Moriya interaction and the cubic anisotropy.