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Complex magnetic ordering in CeGe1.76 studied by neutron diffraction

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 نشر من قبل Andreas Kreyssig
 تاريخ النشر 2014
  مجال البحث فيزياء
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Neutron diffraction measurements on a single crystal of CeGe1.76 reveal a complex series of magnetic transitions at low temperature. At T_N = 7 K, there is a transition from a paramagnetic state at higher temperature to an incommensurate magnetic structure characterized by a magnetic propagation vector (0 0 tau) with tau approx. 1/4 and the magnetic moment along the a axis of the orthorhombic unit cell. Below T_LI = 5 K, the magnetic structure locks in to a commensurate structure with tau = 1/4 and the magnetic moment remains along the a axis. Below T* = 4 K, we find additional half-integer and integer indexed magnetic Bragg peaks consistent with a second commensurately ordered antiferromagnetic state.

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