Nuclear Magnetism of Two Dimensional Solid 3He Adsorbed on Plated Graphite

Nuclear spin exchange in the low density two dimensional quantum solid formed by3He adsorbed on graphite plated by a bilayer of HD has been studied by heat capacity and magnetization measurements. The low densities result in a frustrated magnet with significantly larger effective exchange constants than observed in the antiferromagnetic second layer of3He on bare graphite. Promotion to a fluid overlayer occurs at 6.8 nm−2. A ferromagnetic anomaly is observed in magnetization measurements at 10 nm−2with an effective exchange constant of 1.0 mK, about half the value observed at the corresponding anomaly on bare graphite.