2008/08/22 by D. E. MacLaughlin, Y. Ohta, Yasuo Ohta +9 · 1 citation
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #Atomic physics #Condensed matter physics #Ground state #Hyperfine structure #Magnetic moment #Magnetism #Muon spin spectroscopy #Nuclear materials and radiation effects #Physics #Physics of Superconductivity and Magnetism #Pyrochlore #Quantum mechanics #Quasistatic process #Relaxation (psychology) #cond-mat.str-el
paper · pdf · doi:10.1016/j.physb.2008.11.167
4 pages, 3 figures, to appear in Proc. 11th Int. Conf. on Muon Spin Rotation, Relaxation and Resonance (muSR2008)
arxiv created 2008/08/22 · openalex publication_date 2008/12/07 · arxiv updated 2009/12/01 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
Muon spin relaxation experiments have been performed in the pyrochlore iridate Pr2Ir2O7 for temperatures in the range 0.025-250 K. Kubo-Toyabe relaxation functions are observed up to > 200 K, indicating static magnetism over this temperature range. The T -> 0 static muon spin relaxation rate Delta(0) ~ 8 mus-1 implies a weak quasistatic moment (~0.1 muB). The temperature dependence of Delta is highly non-mean-field-like, decreasing smoothly by orders of magnitude but remaining nonzero below ~150 K. The data rule out ordering of the full Pr3+ CEF ground-state moment (3.0 muB) down to 0.025 K. The weak static magnetism is most likely due to hyperfine-enhanced 141Pr nuclear magnetism. The dynamic relaxation rate lambda increases markedly below ~20 K, probably due to slowing down of spin fluctuations in the spin-liquid state. At low temperatures lambda is strong and temperature-independent, indicative of a high density of low-lying spin excitations as is common in frustrated antiferromagnets.