Coherent magnetic diffraction from the uranium M4 edge in the multi-k magnet, USb

J. A. Lim (1) , E. Blackburn (1) , G. Beutier (2) , F. Livet (2) , N. Magnani (3) , A. Bombardi (4) , R. Caciuffo (3) , G. H. Lander (3)

1 School of Physics and Astronomy
2 SIMaP - Science et Ingénierie des Matériaux et Procédés
3 ITU - JRC Institute for Transuranium Elements [Karlsruhe]
4 DIAMOND Light source

The slow magnetic dynamics, from seconds to kiloseconds, of the canonical 3-k antiferromagnet USb have been probed, using X-ray photon correlation spectroscopy (XPCS). In this work, XPCS is combined with resonant X-ray diffraction to focus on scattering at an antiferromagnetic Bragg peak. High quality coherent magnetic diffraction patterns were recorded (speckle contrast of ~ 88%) and magnetic domains were observed; the number of domains increases on warming to T* ~ 160 K, where the spin waves soften to zero frequency, and again on warming to TN = 218 K. The intensity auto-correlation, g2(t), is primarily static over 1000 s, with a small dynamical process (change of ~ 0.4%) that increases in rate close to the transitions.

Domaines: Science des matériaux [cond-mat.mtrl-sci]

J. A. Lim, E. Blackburn, G. Beutier, F. Livet, N. Magnani, et al.. Coherent magnetic diffraction from the uranium M4 edge in the multi-k magnet, USb. Journal of Physics: Conference Series, 2014, 519, pp.2010. ⟨10.1088/1742-6596/519/1/012010⟩. ⟨hal-01071843⟩