Slightly Co-doped ${\mathrm{MnWO}}_4$ at the lowest 5% Co concentration, for which the multiferroic cycloidal phase becomes a ground state, has been studied in magnetic fields up to 60 T by bulk magnetic and electric polarization measurements along different crystallographic directions. The field induced magnetic transitions up to 12 T and the ways they proceed were tracked also by single-crystal neutron diffraction, and the relevant field induced magnetic structures were identified and refined. The complete magnetoelectric phase diagrams for magnetic fields along distinct directions in relation to the cycloidal spin structure have been constructed for magnetic field values exceeding those necessary to induce a spin-flip transition into the paramagnetic state. Their common feature is the existence of nonpolar sinusoidal phases identified by the disappearance of the electric polarization in a field regime slightly below the spin-flip transition. At lower magnetic fields either continuous or abrupt field induced reorientations of the cycloidal magnetic structures were observed, respectively, for a field direction along the crystallographic $b$ axis or along the easy magnetic axis, and the different character of those transitions has been attributed to specific features in the magnetic anisotropy.

中文翻译：

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具有摆线自旋结构的多铁性Mn0.95Co0.05WO4的磁场诱导相变和相图

轻度共掺杂 ${\mathrm{锰酸锰}}_4$在最高60 T的磁场中，通过沿不同晶体学方向的体磁和电极化测量，研究了在Co浓度最低的5％（最低Co浓度）时，多铁性摆线体相变为基态。还通过单晶中子衍射追踪了高达12 T的磁场感应磁跃迁及其进行的方式，并确定并完善了相关的磁场感应磁结构。已经针对与摆线自旋结构有关的沿不同方向的磁场的完整磁电相图进行了构造，其磁场值超过了诱发自旋翻转转变为顺磁态所需的磁场值。它们的共同特征是存在非极性正弦相，该极性可通过略低于自旋翻转跃迁的电场状态中的电极化消失来识别。在较低的磁场下，沿着晶体学的场方向分别观察到了连续或突变场引起的摆线磁结构的重新取向$b$ 轴或沿易磁轴，并且这些跃迁的不同特征已归因于磁各向异性的特定特征。