2011/09/06 by B. S. Shivaram, Shivaram, B. S., D. G. Hinks +1
Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Physics of Superconductivity and Magnetism #Rare-earth and actinide compounds #Strongly Correlated Electrons (cond-mat.str-el) #cond-mat.str-el
paper · pdf · doi:10.48550/arxiv.1109.1038
5 figs
arxiv created 2011/09/06 · openalex publication_date 2011/09/06 · arxiv updated 2011/09/07 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
Despite several decades of both experimental and theoretical work the nature of the hidden order transition at THO = 17.5 K in URu2Si2 remains enigmatic. We report here low field DC magnetization as well as AC susceptibility measurements performed on single crystals with field along the c-axis. A peak in the first order AC susceptibility is observed at T=16 K in close proximity to the well known change in slope at THO=17.5 K. Third order susceptibility measurements on the other hand reveal a signature only at 16 K with no discernible change at THO. However, both transitions are visible in the fifth order susceptibility. A signature at this lower transition, as a spontaneous ferromagnetic signal, also appears in low field DC magnetization measurements. A similar but larger ferromagnetic response appears at T~35 K. Both these ferromagnetic signatures are suppressed in a small field (B ~ 40 Gauss ||c-axis). The close proximity of the lower signature to the hidden order transition and the simultaneous presence and suppression of a ferromagnetic signature at 35 K could be due to the removal of degeneracy in the complex order-parameter of the hidden order transition due a "symmetry breaking field", at least locally within the crystals of URu2Si2.