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Investigation of the magnetic ground state of GaV$_4$S$_8$ using powder neutron diffraction

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 نشر من قبل Samuel Holt Mr
 تاريخ النشر 2021
  مجال البحث فيزياء
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The magnetic ground state of polycrystalline Neel skyrmion hosting material GaV$_4$S$_8$ has been investigated using ac susceptibility and powder neutron diffraction. In the absence of an applied magnetic field GaV$_4$S$_8$ undergoes a transition from a paramagnetic to a cycloidal state below 13~K and then to a ferromagnetic-like state below 6~K. With evidence from ac susceptibility and powder neutron diffraction, we have identified the commensurate magnetic structure at 1.5 K, with ordered magnetic moments of $0.23(2)~mu_{mathrm{B}}$ on the V1 sites and $0.22(1)~mu_{mathrm{B}}$ on the V2 sites. These moments have ferromagnetic-like alignment but with a 39(8)$^{circ}$ canting of the magnetic moments on the V2 sites away from the V$_4$ cluster. In the incommensurate magnetic phase that exists between 6 and 13 K, we provide a thorough and careful analysis of the cycloidal magnetic structure exhibited by this material using powder neutron diffraction.



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