Angular dependence of metamagnetic transitions in ${\mathrm{HoNi}}_2$ ${\mathrm{B}}_2$ C

Detailed measurements of M(2 K, H, θ) of ${\mathrm{HoNi}}_2$ ${\mathrm{B}}_2$ C, where θ is the angle that the applied field H makes with the [110] axis while remaining perpendicular to the crystallographic c axis, reveal three metamagnetic transitions with angular dependences ${\mathrm{H}}_{\mathrm{c}1\mathrm{}}$ =(4.1±0.1 kG)/cos(θ), ${\mathrm{H}}_{\mathrm{c}2\mathrm{}}$ =8.4±0.2 kG/cos(φ), and ${\mathrm{H}}_{\mathrm{c}3\mathrm{}}$ =(6.6±0.2 kG)/sin(φ), where φ=θ-45 is the angle from the [100] axis. The high-field saturated moment, ${\mathrm{M}}_{\mathrm{sat}}$ ≈10${\mathrm{\mu }}_{\mathrm{B}}$ cosθ is consistent with the local moments being confined to the [110] direction. The locally saturated moments for fields between ${\mathrm{H}}_{\mathrm{ci}}$ (i=1,2,3) also manifest angular dependences that are consistent with combinations of local moments along [110] axes. Analysis of these data lead us to infer that the net distribution of moments is (↑↓↑↓↑↓) for H<${\mathrm{H}}_{\mathrm{c}1\mathrm{}}$ , (↑↑↓↑↑↓) for ${\mathrm{H}}_{\mathrm{c}1\mathrm{}}$ ${\mathrm{H}}_{\mathrm{c}2\mathrm{}}$ , (↑↑→↑↑→) for ${\mathrm{H}}_{\mathrm{c}2\mathrm{}}$ ${\mathrm{H}}_{\mathrm{c}3\mathrm{}}$ , and (↑↑↑↑↑↑) for H>${\mathrm{H}}_{\mathrm{c}3\mathrm{}}$ .