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arXiv · 1407.4067

Tuning the magnetic and structural phase transitions of PrFeAsO via Fe/Ru spin dilution

Yuen Yiu·Pietro Bonfà·Samuele Sanna·Roberto De Renzi·Pietro Carretta·Michael A. McGuire·Ashfia Huq·Stephen E. Nagler
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Abstract

Neutron diffraction and muon spin relaxation measurements are used to obtain a detailed phase diagram of Pr(Fe,Ru)AsO. The isoelectronic substitution of Ru for Fe acts effectively as spin dilution, suppressing both the structural and magnetic phase transitions. The temperature of the tetragonal-orthorhombic structural phase transition decreases gradually as a function of x. Slightly below the transition temperature coherent precessions of the muon spin are observed corresponding to static magnetism, possibly reflecting a significant magneto-elastic coupling in the FeAs layers. Short range order in both the Fe and Pr moments persists for higher levels of x. The static magnetic moments disappear at a concentration coincident with that expected for percolation of the J1-J2 square lattice model.

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Yuen Yiu, Pietro Bonfà, Samuele Sanna, Roberto De Renzi, Pietro Carretta, Michael A. McGuire, Ashfia Huq, Stephen E. Nagler. 2014-07-15. Tuning the magnetic and structural phase transitions of PrFeAsO via Fe/Ru spin dilution. https://doi.org/10.1103/physrevb.90.064515

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