Competition between stripe and checkerboard magnetic instabilities in Mn-doped BaFe2As2

G. S. Tucker; D. K. Pratt; M. G. Kim; S. Ran; A. Thaler; G. E. Granroth; K. Marty; W. Tian; J. L. Zarestky; M. D. Lumsden; S. L. Bud'ko; P. C. Canfield; A. Kreyssig; A. I. Goldman; R. J. McQueeney

doi:10.1103/physrevb.86.020503

arXiv · 1206.3486

Competition between stripe and checkerboard magnetic instabilities in Mn-doped BaFe2As2

G. S. Tucker·D. K. Pratt·M. G. Kim·S. Ran·A. Thaler·G. E. Granroth·K. Marty·W. Tian·J. L. Zarestky·M. D. Lumsden·S. L. Bud'ko·P. C. Canfield·A. Kreyssig·A. I. Goldman·R. J. McQueeney

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Abstract

Inelastic neutron scattering measurements on Ba(Fe0.925Mn0.075)2As2 manifest spin fluctuations at two different wavevectors in the Fe square lattice, (1/2,0) and (1/2,1/2), corresponding to the expected stripe spin-density wave order and checkerboard antiferromagnetic order, respectively. Below T_N=80 K, long-range stripe magnetic ordering occurs and sharp spin wave excitations appear at (1/2,0) while broad and diffusive spin fluctuations remain at (1/2,1/2) at all temperatures. Low concentrations of Mn dopants nucleate local moment spin fluctuations at (1/2,1/2) that compete with itinerant spin fluctuations at (1/2,0) and may disrupt the development of superconductivity.

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G. S. Tucker, D. K. Pratt, M. G. Kim, S. Ran, A. Thaler, G. E. Granroth, K. Marty, W. Tian, J. L. Zarestky, M. D. Lumsden, S. L. Bud'ko, P. C. Canfield, A. Kreyssig, A. I. Goldman, R. J. McQueeney. 2012-06-15. Competition between stripe and checkerboard magnetic instabilities in Mn-doped BaFe2As2. https://doi.org/10.1103/physrevb.86.020503

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