Interplay between Fe and Nd magnetism in NdFeAsO single crystals

W. Tian; W. Ratcliff II; M. G. Kim; J. -Q. Yan; P. A. Kienzle; Q. Huang; B. Jensen; K. W. Dennis; R. W. McCallum; T. A. Lograsso; R. J. McQueeney; A. I. Goldman; J. W. Lynn; A. Kreyssig

doi:10.1103/physrevb.82.060514

arXiv · 1006.1135

Interplay between Fe and Nd magnetism in NdFeAsO single crystals

W. Tian·W. Ratcliff II·M. G. Kim·J. -Q. Yan·P. A. Kienzle·Q. Huang·B. Jensen·K. W. Dennis·R. W. McCallum·T. A. Lograsso·R. J. McQueeney·A. I. Goldman·J. W. Lynn·A. Kreyssig

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Abstract

The structural and magnetic phase transitions have been studied on NdFeAsO single crystals by neutron and x-ray diffraction complemented by resistivity and specific heat measurements. Two low-temperature phase transitions have been observed in addition to the tetragonal-to-orthorhombic transition at T_S = 142 K and the onset of antiferromagnetic (AFM) Fe order below T_N = 137 K. The Fe moments order AFM in the well-known stripe-like structure in the (ab) plane, but change from AFM to ferromagnetic (FM) arrangement along the c direction below T* = 15 K accompanied by the onset of Nd AFM order below T_Nd = 6 K with this same AFM configuration. The iron magnetic order-order transition in NdFeAsO accentuates the Nd-Fe interaction and the delicate balance of c-axis exchange couplings that results in AFM in LaFeAsO and FM in CeFeAsO and PrFeAsO.

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W. Tian, W. Ratcliff II, M. G. Kim, J. -Q. Yan, P. A. Kienzle, Q. Huang, B. Jensen, K. W. Dennis, R. W. McCallum, T. A. Lograsso, R. J. McQueeney, A. I. Goldman, J. W. Lynn, A. Kreyssig. 2010-08-15. Interplay between Fe and Nd magnetism in NdFeAsO single crystals. https://doi.org/10.1103/physrevb.82.060514

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