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Element-specific field-induced spin reorientation and an unusual tetracritical point in MnCr2S4

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 نشر من قبل Shingo Yamamoto
 تاريخ النشر 2020
  مجال البحث فيزياء
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The ferrimagnetic spinel MnCr2S4 shows a variety of magnetic-field-induced phase transitions owing to bond frustration and strong spin-lattice coupling. However, the site-resolved magnetic properties at the respective field-induced phases in high magnetic fields remain elusive. Our soft x-ray magnetic circular dichroism studies up to 40 T directly evidence element-selective magnetic-moment reorientations in the field-induced phases. The complex magnetic structures are further supported by entropy changes extracted from magnetocaloric-effect measurements. Moreover, thermodynamic experiments reveal an unusual tetracritical point in the H-T phase diagram of MnCr2S4 due to strong spin-lattice coupling.

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