Spin reorientation in TlFe1.6Se2 with complete vacancy ordering

Andrew F. May; Michael A. McGuire; Huibo Cao; Ilya Sergueev; Claudia Cantoni; Bryan C. Chakoumakos; David S. Parker; Brian C. Sales

doi:10.1103/physrevlett.109.077003

arXiv · 1207.1318

Spin reorientation in TlFe1.6Se2 with complete vacancy ordering

Andrew F. May·Michael A. McGuire·Huibo Cao·Ilya Sergueev·Claudia Cantoni·Bryan C. Chakoumakos·David S. Parker·Brian C. Sales

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Abstract

The relationship between vacancy ordering and magnetism in TlFe1.6Se2 has been investigated via single crystal neutron diffraction, nuclear forward scattering, and transmission electron microscopy. The examination of chemically and structurally homogenous crystals allows the true ground state to be revealed, which is characterized by Fe moments lying in the ab-plane below 100K. This is in sharp contrast to crystals containing regions of order and disorder, where a competition between c-axis and ab-plane orientations of the moments is observed. The properties of partially-disordered TlFe1.6Se2 are therefore not associated with solely the ordered or disordered regions. This contrasts the viewpoint that phase separation results in independent physical properties in intercalated iron selenides, suggesting a coupling between ordered and disordered regions may play an important role in the superconducting analogues.

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Andrew F. May, Michael A. McGuire, Huibo Cao, Ilya Sergueev, Claudia Cantoni, Bryan C. Chakoumakos, David S. Parker, Brian C. Sales. 2012-07-05. Spin reorientation in TlFe1.6Se2 with complete vacancy ordering. https://doi.org/10.1103/physrevlett.109.077003

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