2022/10/18 by K. Somesh, S. S. Islam, Somesh, K. +15 · 2 citations
Materials Science · Physics and Astronomy · #Advanced Condensed Matter Physics #FOS: Physical sciences #Iron-based superconductors research #Materials Science (cond-mat.mtrl-sci) #Physics of Superconductivity and Magnetism #Strongly Correlated Electrons (cond-mat.str-el)
paper · pdf · doi:10.48550/arxiv.2210.09724
openalex publication_date 2022/10/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We present the ground state properties of a new quantum antiferromagnet YbBO3 in which the isotropic Yb3+ triangular layers are separated by a non-magnetic layer of partially occupied B and O(2) sites. The magnetization and heat capacity data establish a spin-orbit entangled effective spin J\rm eff = 1/2 state of Yb3+ ions at low temperatures, interacting antiferromagnetically with an intra-layer coupling J/k\rm B ≃ 0.53 K. The absence of oscillations and a 1/3 tail in the zero-field muon asymmetries rule out the onset of magnetic long-range-order as well as spin-freezing down to 20~mK. An anomalous broad maximum in the temperature dependent heat capacity with a unusually reduced value and a broad anomaly in zero-field muon depolarization rate centered at T^*≃ 0.7 \fracJk\rm B provide compelling evidence for a wide fluctuating regime (0.182 ≤ T/J ≤ 1.63) with slow relaxation. We infer that the fluctuating regime is a universal feature of a highly frustrated triangular lattice antiferromagnets while the absence of magnetic long-range-order is due to perfect two-dimensionality of the spin-lattice protected by non-magnetic site disorder.