Multiple metamagnetic transitions induced by high magnetic field in DyBi

Abstract

The rare-earth monopnictide compounds have recently received considerable attention in condensed matter physics because of their correlation between magnetism, crystallographic structure, and transport. Here, we report experimental observations of high-magnetic-field-induced multiple metamagnetic transitions and magnetic structures in DyBi single crystals. The external field up to 32 T is applied in three distinct crystallographic directions as $H//[001]$, $H//[011]$, and $H//[111]$, which reveals anisotropic magnetism as well as multiple metamagnetic transitions. Two field-induced magnetic phase transitions at 3.7 T and 4.9 T along $H//[001]$, two at 3.8 T and 24 T along $H//[011]$, and one at 3.8 T along $H//[111]$ are identified. In order to unveil the nature of magnetic interaction in DyBi, the critical behavior analysis for $H//$[001], a direction with typical magnetism and transitions, is performed. The yielded critical exponents $\ensuremath{\beta}=0.234(8)$, $\ensuremath{\gamma}=0.904(3)$, and $\ensuremath{\delta}=5.03(2)$ agree well with the theoretical prediction of a tricritical mean-field model, indicating a field-induced tricritical phenomenon in this system. Comprehensive magnetic phase diagrams for $H//[001]$, $H//[011]$, and $H//[111]$ are constructed based on detailed magnetization measurement and scaling, which reveal multiple phases such as NiO-type antiferromagnetic (AFM), HoP-type AFM, forced ferromagnetic (FFM), and paramagnetic (PM) phases. Two tricritical points (TCPs) are determined at the intersections of the AFM, FFM, and PM phases, with TCP = (8.6 K, 85 kOe) for $H//$[001] and (16.8 K, 243 kOe) for $H//$[011]. The recognition of multiple phases suggests delicate and complex competition and balance between variable couplings in this system.